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SQLite training in Houston TX on 2019-11-05 (details)
Part of the 2019 Tcl Conference

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Overview
Comment:Revised date/time functions - now broken out into a separate source file. See the DateAndTimeFunctions wiki page for additional information. (CVS 1116)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 68ef9b45bd3abdedf3721011ad0fb22e8735e721
User & Date: drh 2003-11-01 01:53:54
Context
2003-11-08
12:07
Added information on MySQL 4.0.16 to the NULL-handling survey. (CVS 1117) check-in: e22e3ab5 user: drh tags: trunk
2003-11-01
01:53
Revised date/time functions - now broken out into a separate source file. See the DateAndTimeFunctions wiki page for additional information. (CVS 1116) check-in: 68ef9b45 user: drh tags: trunk
2003-10-30
07:00
Fork the tree for project "shrike" (CVS 1118) check-in: 181260c0 user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to Makefile.in.

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endif

# You should not have to change anything below this line
###############################################################################

# Object files for the SQLite library.
#
LIBOBJ = attach.lo auth.lo btree.lo build.lo copy.lo \
         delete.lo expr.lo func.lo hash.lo insert.lo \
         main.lo opcodes.lo os.lo pager.lo parse.lo pragma.lo \
         printf.lo random.lo select.lo table.lo tokenize.lo \
         update.lo util.lo vacuum.lo vdbe.lo vdbeaux.lo \
         where.lo trigger.lo

# Only build the in-core DB if it is required.
................................................................................
  $(TOP)/src/attach.c \
  $(TOP)/src/auth.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/btree.h \
  $(TOP)/src/btree_rb.c \
  $(TOP)/src/build.c \
  $(TOP)/src/copy.c \

  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/main.c \
................................................................................

where.lo:	$(TOP)/src/where.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/where.c

copy.lo:	$(TOP)/src/copy.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/copy.c




delete.lo:	$(TOP)/src/delete.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/delete.c

expr.lo:	$(TOP)/src/expr.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/expr.c

func.lo:	$(TOP)/src/func.c $(HDR)







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endif

# You should not have to change anything below this line
###############################################################################

# Object files for the SQLite library.
#
LIBOBJ = attach.lo auth.lo btree.lo build.lo copy.lo date.lo \
         delete.lo expr.lo func.lo hash.lo insert.lo \
         main.lo opcodes.lo os.lo pager.lo parse.lo pragma.lo \
         printf.lo random.lo select.lo table.lo tokenize.lo \
         update.lo util.lo vacuum.lo vdbe.lo vdbeaux.lo \
         where.lo trigger.lo

# Only build the in-core DB if it is required.
................................................................................
  $(TOP)/src/attach.c \
  $(TOP)/src/auth.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/btree.h \
  $(TOP)/src/btree_rb.c \
  $(TOP)/src/build.c \
  $(TOP)/src/copy.c \
  $(TOP)/src/date.c \
  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/main.c \
................................................................................

where.lo:	$(TOP)/src/where.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/where.c

copy.lo:	$(TOP)/src/copy.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/copy.c

date.lo:	$(TOP)/src/date.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/date.c

delete.lo:	$(TOP)/src/delete.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/delete.c

expr.lo:	$(TOP)/src/expr.c $(HDR)
	$(LIBTOOL) $(TCC) -c $(TOP)/src/expr.c

func.lo:	$(TOP)/src/func.c $(HDR)

Changes to main.mk.

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# This is how we compile
#
TCCX = $(TCC) $(OPTS) $(THREADSAFE) $(USLEEP) -I. -I$(TOP)/src

# Object files for the SQLite library.
#
LIBOBJ = attach.o auth.o btree.o btree_rb.o build.o copy.o delete.o \
         expr.o func.o hash.o insert.o \
         main.o opcodes.o os.o pager.o parse.o pragma.o printf.o random.o \
         select.o table.o tokenize.o trigger.o update.o util.o \
         vacuum.o vdbe.o vdbeaux.o where.o tclsqlite.o

# All of the source code files.
#
................................................................................
  $(TOP)/src/attach.c \
  $(TOP)/src/auth.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/btree.h \
  $(TOP)/src/btree_rb.c \
  $(TOP)/src/build.c \
  $(TOP)/src/copy.c \

  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/main.c \
................................................................................
	$(TCCX) -c $(TOP)/src/vdbeaux.c

where.o:	$(TOP)/src/where.c $(HDR)
	$(TCCX) -c $(TOP)/src/where.c

copy.o:	$(TOP)/src/copy.c $(HDR)
	$(TCCX) -c $(TOP)/src/copy.c




delete.o:	$(TOP)/src/delete.c $(HDR)
	$(TCCX) -c $(TOP)/src/delete.c

expr.o:	$(TOP)/src/expr.c $(HDR)
	$(TCCX) -c $(TOP)/src/expr.c








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# This is how we compile
#
TCCX = $(TCC) $(OPTS) $(THREADSAFE) $(USLEEP) -I. -I$(TOP)/src

# Object files for the SQLite library.
#
LIBOBJ = attach.o auth.o btree.o btree_rb.o build.o copy.o date.o delete.o \
         expr.o func.o hash.o insert.o \
         main.o opcodes.o os.o pager.o parse.o pragma.o printf.o random.o \
         select.o table.o tokenize.o trigger.o update.o util.o \
         vacuum.o vdbe.o vdbeaux.o where.o tclsqlite.o

# All of the source code files.
#
................................................................................
  $(TOP)/src/attach.c \
  $(TOP)/src/auth.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/btree.h \
  $(TOP)/src/btree_rb.c \
  $(TOP)/src/build.c \
  $(TOP)/src/copy.c \
  $(TOP)/src/date.c \
  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/main.c \
................................................................................
	$(TCCX) -c $(TOP)/src/vdbeaux.c

where.o:	$(TOP)/src/where.c $(HDR)
	$(TCCX) -c $(TOP)/src/where.c

copy.o:	$(TOP)/src/copy.c $(HDR)
	$(TCCX) -c $(TOP)/src/copy.c

date.o:	$(TOP)/src/date.c $(HDR)
	$(TCCX) -c $(TOP)/src/date.c

delete.o:	$(TOP)/src/delete.c $(HDR)
	$(TCCX) -c $(TOP)/src/delete.c

expr.o:	$(TOP)/src/expr.c $(HDR)
	$(TCCX) -c $(TOP)/src/expr.c

Added src/date.c.











































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































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/*
** 2003 October 31
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.1 2003/11/01 01:53:54 drh Exp $
**
** NOTES:
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system.
**
** 1970-01-01 00:00:00 is JD 2440587.5
** 2000-01-01 00:00:00 is JD 2451544.5
**
** This implemention requires years to be expressed as a 4-digit number
** which means that only dates between 0000-01-01 and 9999-12-31 can
** be represented, even though julian day numbers allow a much wider
** range of dates.
**
** The Gregorian calendar system is used for all dates and times,
** even those that predate the Gregorian calendar.  Historians usually
** use the Julian calendar for dates prior to 1582-10-15 and for some
** dates afterwards, depending on locale.  Beware of this difference.
**
** The conversion algorithms are implemented based on descriptions
** in the following text:
**
**      Jean Meeus
**      Astronomical Algorithms, 2nd Edition, 1998
**      ISBM 0-943396-61-1
**      Willmann-Bell, Inc
**      Richmond, Virginia (USA)
*/
#ifndef SQLITE_OMIT_DATETIME_FUNCS
#include <ctype.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"
#include "os.h"

/*
** A structure for holding a single date and time.
*/
typedef struct DateTime DateTime;
struct DateTime {
  double rJD;      /* The julian day number */
  int Y, M, D;     /* Year, month, and day */
  int h, m;        /* Hour and minutes */
  int tz;          /* Timezone offset in minutes */
  double s;        /* Seconds */
  char validYMD;   /* True if Y,M,D are valid */
  char validHMS;   /* True if h,m,s are valid */
  char validJD;    /* True if rJD is valid */
  char validTZ;    /* True if tz is valid */
};


/*
** Convert N digits from zDate into an integer.  Return
** -1 if zDate does not begin with N digits.
*/
static int getDigits(const char *zDate, int N){
  int val = 0;
  while( N-- ){
    if( !isdigit(*zDate) ) return -1;
    val = val*10 + *zDate - '0';
    zDate++;
  }
  return val;
}

/*
** Read text from z[] and convert into a floating point number.  Return
** the number of digits converted.
*/
static int getValue(const char *z, double *pR){
  double r = 0.0;
  double rDivide = 1.0;
  int isNeg = 0;
  int nChar = 0;
  if( *z=='+' ){
    z++;
    nChar++;
  }else if( *z=='-' ){
    z++;
    isNeg = 1;
    nChar++;
  }
  if( !isdigit(*z) ) return 0;
  while( isdigit(*z) ){
    r = r*10.0 + *z - '0';
    nChar++;
    z++;
  }
  if( *z=='.' && isdigit(z[1]) ){
    z++;
    nChar++;
    while( isdigit(*z) ){
      r = r*10.0 + *z - '0';
      rDivide *= 10.0;
      nChar++;
      z++;
    }
    r /= rDivide;
  }
  if( *z!=0 && !isspace(*z) ) return 0;
  *pR = isNeg ? -r : r;
  return nChar;
}

/*
** Parse a timezone extension on the end of a date-time.
** The extension is of the form:
**
**        (+/-)HH:MM
**
** If the parse is successful, write the number of minutes
** of change in *pnMin and return 0.  If a parser error occurs,
** return 0.
**
** A missing specifier is not considered an error.
*/
static int parseTimezone(const char *zDate, DateTime *p){
  int sgn = 0;
  int nHr, nMn;
  while( isspace(*zDate) ){ zDate++; }
  p->tz = 0;
  if( *zDate=='-' ){
    sgn = -1;
  }else if( *zDate=='+' ){
    sgn = +1;
  }else{
    return *zDate!=0;
  }
  zDate++;
  nHr = getDigits(zDate, 2);
  if( nHr<0 || nHr>14 ) return 1;
  zDate += 2;
  if( zDate[0]!=':' ) return 1;
  zDate++;
  nMn = getDigits(zDate, 2);
  if( nMn<0 || nMn>59 ) return 1;
  zDate += 2;
  p->tz = sgn*(nMn + nHr*60);
  while( isspace(*zDate) ){ zDate++; }
  return *zDate!=0;
}

/*
** Parse times of the form HH:MM or HH:MM:SS or HH:MM:SS.FFFF.
** The HH, MM, and SS must each be exactly 2 digits.  The
** fractional seconds FFFF can be one or more digits.
**
** Return 1 if there is a parsing error and 0 on success.
*/
static int parseHhMmSs(const char *zDate, DateTime *p){
  int h, m, s;
  double ms = 0.0;
  h = getDigits(zDate, 2);
  if( h<0 || zDate[2]!=':' ) return 1;
  zDate += 3;
  m = getDigits(zDate, 2);
  if( m<0 || m>59 ) return 1;
  zDate += 2;
  if( *zDate==':' ){
    s = getDigits(&zDate[1], 2);
    if( s<0 || s>59 ) return 1;
    zDate += 3;
    if( *zDate=='.' && isdigit(zDate[1]) ){
      double rScale = 1.0;
      zDate++;
      while( isdigit(*zDate) ){
        ms = ms*10.0 + *zDate - '0';
        rScale *= 10.0;
        zDate++;
      }
      ms /= rScale;
    }
  }else{
    s = 0;
  }
  p->validJD = 0;
  p->validHMS = 1;
  p->h = h;
  p->m = m;
  p->s = s + ms;
  if( parseTimezone(zDate, p) ) return 1;
  p->validTZ = p->tz!=0;
  return 0;
}

/*
** Convert from YYYY-MM-DD HH:MM:SS to julian day.  We always assume
** that the YYYY-MM-DD is according to the Gregorian calendar.
**
** Reference:  Meeus page 61
*/
static void computeJD(DateTime *p){
  int Y, M, D, A, B, X1, X2;

  if( p->validJD ) return;
  if( p->validYMD ){
    Y = p->Y;
    M = p->M;
    D = p->D;
  }else{
    Y = 2000;
    M = 1;
    D = 1;
  }
  if( M<=2 ){
    Y--;
    M += 12;
  }
  A = Y/100;
  B = 2 - A + (A/4);
  X1 = 365.25*(Y+4716);
  X2 = 30.6001*(M+1);
  p->rJD = X1 + X2 + D + B - 1524.5;
  p->validJD = 1;
  p->validYMD = 0;
  if( p->validHMS ){
    p->rJD += (p->h*3600.0 + p->m*60.0 + p->s)/86400.0;
    if( p->validTZ ){
      p->rJD += p->tz*60/86400.0;
      p->validHMS = 0;
      p->validTZ = 0;
    }
  }
}

/*
** Parse dates of the form
**
**     YYYY-MM-DD HH:MM:SS.FFF
**     YYYY-MM-DD HH:MM:SS
**     YYYY-MM-DD HH:MM
**     YYYY-MM-DD
**
** Write the result into the DateTime structure and return 0
** on success and 1 if the input string is not a well-formed
** date.
*/
static int parseYyyyMmDd(const char *zDate, DateTime *p){
  int Y, M, D;

  Y = getDigits(zDate, 4);
  if( Y<0 || zDate[4]!='-' ) return 1;
  zDate += 5;
  M = getDigits(zDate, 2);
  if( M<=0 || M>12 || zDate[2]!='-' ) return 1;
  zDate += 3;
  D = getDigits(zDate, 2);
  if( D<=0 || D>31 ) return 1;
  zDate += 2;
  while( isspace(*zDate) ){ zDate++; }
  if( isdigit(*zDate) ){
    if( parseHhMmSs(zDate, p) ) return 1;
  }else if( *zDate==0 ){
    p->validHMS = 0;
  }else{
    return 1;
  }
  p->validJD = 0;
  p->validYMD = 1;
  p->Y = Y;
  p->M = M;
  p->D = D;
  if( p->validTZ ){
    computeJD(p);
  }
  return 0;
}

/*
** Attempt to parse the given string into a Julian Day Number.  Return
** the number of errors.
**
** The following are acceptable forms for the input string:
**
**      YYYY-MM-DD HH:MM:SS.FFF  +/-HH:MM
**      DDDD.DD 
**      now
**
** In the first form, the +/-HH:MM is always optional.  The fractional
** seconds extension (the ".FFF") is optional.  The seconds portion
** (":SS.FFF") is option.  The year and date can be omitted as long
** as there is a time string.  The time string can be omitted as long
** as there is a year and date.
*/
static int parseDateOrTime(const char *zDate, DateTime *p){
  int i;
  memset(p, 0, sizeof(*p));
  for(i=0; isdigit(zDate[i]); i++){}
  if( i==4 && zDate[i]=='-' ){
    return parseYyyyMmDd(zDate, p);
  }else if( i==2 && zDate[i]==':' ){
    return parseHhMmSs(zDate, p);
    return 0;
  }else if( i==0 && sqliteStrICmp(zDate,"now")==0 ){
    double r;
    if( sqliteOsCurrentTime(&r)==0 ){
      p->rJD = r;
      p->validJD = 1;
      return 0;
    }
    return 1;
  }else if( sqliteIsNumber(zDate) ){
    p->rJD = atof(zDate);
    p->validJD = 1;
    return 0;
  }
  return 1;
}

/*
** Compute the Year, Month, and Day from the julian day number.
*/
static void computeYMD(DateTime *p){
  int Z, A, B, C, D, E, X1;
  if( p->validYMD ) return;
  Z = p->rJD + 0.5;
  A = (Z - 1867216.25)/36524.25;
  A = Z + 1 + A - (A/4);
  B = A + 1524;
  C = (B - 122.1)/365.25;
  D = 365.25*C;
  E = (B-D)/30.6001;
  X1 = 30.6001*E;
  p->D = B - D - X1;
  p->M = E<14 ? E-1 : E-13;
  p->Y = p->M>2 ? C - 4716 : C - 4715;
  p->validYMD = 1;
}

/*
** Compute the Hour, Minute, and Seconds from the julian day number.
*/
static void computeHMS(DateTime *p){
  int Z, s;
  if( p->validHMS ) return;
  Z = p->rJD + 0.5;
  s = (p->rJD + 0.5 - Z)*86400000.0 + 0.5;
  p->s = 0.001*s;
  s = p->s;
  p->s -= s;
  p->h = s/3600;
  s -= p->h*3600;
  p->m = s/60;
  p->s += s - p->m*60;
  p->validHMS = 1;
}

/*
** Process a modifier to a date-time stamp.  The modifiers are
** as follows:
**
**     NNN days
**     NNN hours
**     NNN minutes
**     NNN.NNNN seconds
**     NNN months
**     NNN years
**     start of month
**     start of year
**     start of week
**     start of day
**     weekday N
**     unixepoch
**
** Return 0 on success and 1 if there is any kind of error.
*/
static int parseModifier(const char *zMod, DateTime *p){
  int rc = 1;
  int n;
  double r;
  char z[30];
  for(n=0; n<sizeof(z)-1; n++){
    z[n] = tolower(zMod[n]);
  }
  z[n] = 0;
  switch( z[0] ){
    case 'u': {
      /*
      **    unixepoch
      **
      ** Treat the current value of p->rJD as the number of
      ** seconds since 1970.  Convert to a real julian day number.
      */
      if( strcmp(z, "unixepoch")==0 && p->validJD ){
        p->rJD = p->rJD/86400.0 + 2440587.5;
        p->validYMD = 0;
        p->validHMS = 0;
        p->validTZ = 0;
        rc = 0;
      }
      break;
    }
    case 'w': {
      /*
      **    weekday N
      **
      ** Move the date to the beginning of the next occurrance of
      ** weekday N where 0==Sunday, 1==Monday, and so forth.  If the
      ** date is already on the appropriate weekday, this is equivalent
      ** to "start of day".
      */
      if( strncmp(z, "weekday ", 8)==0 && getValue(&z[8],&r)>0
                 && (n=r)==r && n>=0 && r<7 ){
        int Z;
        computeYMD(p);
        p->validHMS = 0;
        p->validTZ = 0;
        p->validJD = 0;
        computeJD(p);
        Z = p->rJD + 1.5;
        Z %= 7;
        if( Z>n ) Z -= 7;
        p->rJD += n - Z;
        p->validYMD = 0;
        p->validHMS = 0;
        rc = 0;
      }
      break;
    }
    case 's': {
      /*
      **    start of TTTTT
      **
      ** Move the date backwards to the beginning of the current day,
      ** or month or year.
      */
      if( strncmp(z, "start of ", 9)!=0 ) break;
      zMod = &z[9];
      computeYMD(p);
      p->validHMS = 1;
      p->h = p->m = 0;
      p->s = 0.0;
      p->validTZ = 0;
      p->validJD = 0;
      if( strcmp(zMod,"month")==0 ){
        p->D = 1;
        rc = 0;
      }else if( strcmp(zMod,"year")==0 ){
        computeYMD(p);
        p->M = 1;
        p->D = 1;
        rc = 0;
      }else if( strcmp(zMod,"day")==0 ){
        rc = 0;
      }
      break;
    }
    case '+':
    case '-':
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9': {
      n = getValue(z, &r);
      if( n<=0 ) break;
      zMod = &z[n];
      while( isspace(zMod[0]) ) zMod++;
      n = strlen(zMod);
      if( n>10 || n<3 ) break;
      strcpy(z, zMod);
      if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
      computeJD(p);
      rc = 0;
      if( n==3 && strcmp(z,"day")==0 ){
        p->rJD += r;
      }else if( n==4 && strcmp(z,"hour")==0 ){
        computeJD(p);
        p->rJD += r/24.0;
      }else if( n==6 && strcmp(z,"minute")==0 ){
        computeJD(p);
        p->rJD += r/(24.0*60.0);
      }else if( n==6 && strcmp(z,"second")==0 ){
        computeJD(p);
        p->rJD += r/(24.0*60.0*60.0);
      }else if( n==5 && strcmp(z,"month")==0 ){
        int x, y;
        computeYMD(p);
        p->M += r;
        x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
        p->Y += x;
        p->M -= x*12;
        p->validJD = 0;
        computeJD(p);
        y = r;
        if( y!=r ){
          p->rJD += (r - y)*30.0;
        }
      }else if( n==4 && strcmp(z,"year")==0 ){
        computeYMD(p);
        p->Y += r;
        p->validJD = 0;
        computeJD(p);
      }else{
        rc = 1;
      }
      p->validYMD = 0;
      p->validHMS = 0;
      p->validTZ = 0;
      break;
    }
    default: {
      break;
    }
  }
  return rc;
}

/*
** Process time function arguments.  argv[0] is a date-time stamp.
** argv[1] and following are modifiers.  Parse them all and write
** the resulting time into the DateTime structure p.  Return 0
** on success and 1 if there are any errors.
*/
static int isDate(int argc, const char **argv, DateTime *p){
  int i;
  if( argc==0 ) return 1;
  if( parseDateOrTime(argv[0], p) ) return 1;
  for(i=1; i<argc; i++){
    if( parseModifier(argv[i], p) ) return 1;
  }
  return 0;
}


/*
** The following routines implement the various date and time functions
** of SQLite.
*/

/*
**    julianday( TIMESTRING, MOD, MOD, ...)
**
** Return the julian day number of the date specified in the arguments
*/
static void juliandayFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x)==0 ){
    computeJD(&x);
    sqlite_set_result_double(context, x.rJD);
  }
}

/*
**    datetime( TIMESTRING, MOD, MOD, ...)
**
** Return YYYY-MM-DD HH:MM:SS
*/
static void datetimeFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x)==0 ){
    char zBuf[100];
    computeYMD(&x);
    computeHMS(&x);
    sprintf(zBuf, "%04d-%02d-%02d %02d:%02d:%02d",x.Y, x.M, x.D, x.h, x.m,
           (int)(x.s));
    sqlite_set_result_string(context, zBuf, -1);
  }
}

/*
**    time( TIMESTRING, MOD, MOD, ...)
**
** Return HH:MM:SS
*/
static void timeFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x)==0 ){
    char zBuf[100];
    computeHMS(&x);
    sprintf(zBuf, "%02d:%02d:%02d", x.h, x.m, (int)x.s);
    sqlite_set_result_string(context, zBuf, -1);
  }
}

/*
**    date( TIMESTRING, MOD, MOD, ...)
**
** Return YYYY-MM-DD
*/
static void dateFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x)==0 ){
    char zBuf[100];
    computeYMD(&x);
    sprintf(zBuf, "%04d-%02d-%02d", x.Y, x.M, x.D);
    sqlite_set_result_string(context, zBuf, -1);
  }
}

/*
**    strftime( FORMAT, TIMESTRING, MOD, MOD, ...)
**
** Return a string described by FORMAT.  Conversions as follows:
**
**   %d  day of month
**   %f  ** fractional seconds  SS.SSS
**   %H  hour 00-24
**   %j  day of year 000-366
**   %J  ** Julian day number
**   %m  month 01-12
**   %M  minute 00-59
**   %s  seconds since 1970-01-01
**   %S  seconds 00-59
**   %w  day of week 0-6  sunday==0
**   %W  week of year 00-53
**   %Y  year 0000-9999
**   %%  %
*/
static void strftimeFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  int n, i, j;
  char *z;
  const char *zFmt = argv[0];
  char zBuf[100];
  if( isDate(argc-1, argv+1, &x) ) return;
  for(i=0, n=1; zFmt[i]; i++, n++){
    if( zFmt[i]=='%' ){
      switch( zFmt[i+1] ){
        case 'd':
        case 'H':
        case 'm':
        case 'M':
        case 'S':
        case 'W':
          n++;
          /* fall thru */
        case 'w':
        case '%':
          break;
        case 'f':
          n += 8;
          break;
        case 'j':
          n += 3;
          break;
        case 'Y':
          n += 8;
          break;
        case 's':
        case 'J':
          n += 50;
          break;
        default:
          return;  /* ERROR.  return a NULL */
      }
      i++;
    }
  }
  if( n<sizeof(zBuf) ){
    z = zBuf;
  }else{
    z = sqliteMalloc( n );
    if( z==0 ) return;
  }
  computeJD(&x);
  computeYMD(&x);
  computeHMS(&x);
  for(i=j=0; zFmt[i]; i++){
    if( zFmt[i]!='%' ){
      z[j++] = zFmt[i];
    }else{
      i++;
      switch( zFmt[i] ){
        case 'd':  sprintf(&z[j],"%02d",x.D); j+=2; break;
        case 'f': {
          int s = x.s;
          int ms = (x.s - s)*1000.0;
          sprintf(&z[j],"%02d.%03d",s,ms);
          j += strlen(&z[j]);
          break;
        }
        case 'H':  sprintf(&z[j],"%02d",x.h); j+=2; break;
        case 'W': /* Fall thru */
        case 'j': {
          int n;
          DateTime y = x;
          y.validJD = 0;
          y.M = 1;
          y.D = 1;
          computeJD(&y);
          n = x.rJD - y.rJD + 1;
          if( zFmt[i]=='W' ){
            sprintf(&z[j],"%02d",(n+6)/7);
            j += 2;
          }else{
            sprintf(&z[j],"%03d",n);
            j += 3;
          }
          break;
        }
        case 'J':  sprintf(&z[j],"%.16g",x.rJD); j+=strlen(&z[j]); break;
        case 'm':  sprintf(&z[j],"%02d",x.M); j+=2; break;
        case 'M':  sprintf(&z[j],"%02d",x.m); j+=2; break;
        case 's': {
          sprintf(&z[j],"%d",(int)((x.rJD-2440587.5)*86400.0));
          j += strlen(&z[j]);
          break;
        }
        case 'S':  sprintf(&z[j],"%02d",(int)x.s); j+=2; break;
        case 'w':  z[j++] = (((int)(x.rJD+1.5)) % 7) + '0'; break;
        case 'Y':  sprintf(&z[j],"%04d",x.Y); j+=strlen(&z[j]); break;
        case '%':  z[j++] = '%'; break;
      }
    }
  }
  z[j] = 0;
  sqlite_set_result_string(context, z, -1);
  if( z!=zBuf ){
    sqliteFree(z);
  }
}


#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */

/*
** This function registered all of the above C functions as SQL
** functions.  This should be the only routine in this file with
** external linkage.
*/
void sqliteRegisterDateTimeFunctions(sqlite *db){
  static struct {
     char *zName;
     int nArg;
     int dataType;
     void (*xFunc)(sqlite_func*,int,const char**);
  } aFuncs[] = {
#ifndef SQLITE_OMIT_DATETIME_FUNCS
    { "julianday", -1, SQLITE_NUMERIC, juliandayFunc   },
    { "date",      -1, SQLITE_TEXT,    dateFunc        },
    { "time",       1, SQLITE_TEXT,    timeFunc        },
    { "datetime",  -1, SQLITE_TEXT,    datetimeFunc    },
    { "strftime",  -1, SQLITE_TEXT,    strftimeFunc    },
#endif
  };
  int i;

  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
    sqlite_create_function(db, aFuncs[i].zName,
           aFuncs[i].nArg, aFuncs[i].xFunc, 0);
    if( aFuncs[i].xFunc ){
      sqlite_function_type(db, aFuncs[i].zName, aFuncs[i].dataType);
    }
  }
}

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** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.32 2003/10/10 02:09:57 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"
#include "os.h"
................................................................................
    sqlite_set_result_string(context, p->z, strlen(p->z));
  }
  if( p && p->z && p->z!=p->zBuf ){
    sqliteFree(p->z);
  }
}

/****************************************************************************
** Time and date functions.
**
** 1970-01-01 00:00:00 is JD 2440587.5.
** 2000-01-01 00:00:00 is JD 2451544.5
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system.
**
** This implement requires years to be expressed as a 4-digit number
** which means that only dates between 0000-01-01 and 9999-12-31 can
** be represented, even though julian day numbers allow a much wider
** range of dates.
**
** The Gregorian calendar system is used for all dates and times,
** even those that predate the Gregorian calendar.  Historians usually
** use the Julian calendar for dates prior to 1582-10-15 and for some
** dates afterwards, depending on locale.  Beware of this difference.
**
** The conversion algorithms are implemented based on descriptions
** in the following text:
**
**      Jean Meeus
**      Astronomical Algorithms, 2nd Edition, 1998
**      ISBM 0-943396-61-1
**      Willmann-Bell, Inc
**      Richmond, Virginia (USA)
*/
#ifndef SQLITE_OMIT_DATETIME_FUNCS

/*
** Convert N digits from zDate into an integer.  Return
** -1 if zDate does not begin with N digits.
*/
static int getDigits(const char *zDate, int N){
  int val = 0;
  while( N-- ){
    if( !isdigit(*zDate) ) return -1;
    val = val*10 + *zDate - '0';
    zDate++;
  }
  return val;
}

/*
** Parse a timezone extension on the end of a datetime stamp.
** The extension is of the form:
**
**        (+/-)HH:MM
**
** If the parse is successful, write the number of minutes
** of change in *pnMin and return 0.  If a parser error occurs,
** return 0.
**
** A missing specifier is not considered an error.
*/
static int parseTimezone(const char *zDate, int *pnMin){
  int sgn = 0;
  int nHr, nMn;
  while( isspace(*zDate) ){ zDate++; }
  *pnMin = 0;
  if( *zDate=='-' ){
    sgn = -1;
  }else if( *zDate=='+' ){
    sgn = +1;
  }else{
    return *zDate!=0;
  }
  zDate++;
  nHr = getDigits(zDate, 2);
  if( nHr<0 || nHr>14 ) return 1;
  zDate += 2;
  if( zDate[0]!=':' ) return 1;
  zDate++;
  nMn = getDigits(zDate, 2);
  if( nMn<0 || nMn>59 ) return 1;
  zDate += 2;
  *pnMin = sgn*(nMn + nHr*60);
  while( isspace(*zDate) ){ *zDate++; }
  return *zDate!=0;
}

/*
** Parse times of the form HH:MM or HH:MM:SS or HH:MM:SS.FFFF.
** The HH, MM, and SS must each be exactly 2 digits.  The
** fractional seconds FFFF can be one or more digits.
**
** The time string can be followed by an optional timezone specifier
** of the following form:  (+/-)HH:MM.
**
** Whatever the format, the string is converted into a julian
** day number and stored in *prJD.
**
** Return 1 if there is a parsing error and 0 on success.
*/
static int parseHhMmSs(const char *zDate, double *prJD){
  int h, m, s, tz;
  double ms = 0.0;
  h = getDigits(zDate, 2);
  if( h<0 || zDate[2]!=':' ) return 1;
  zDate += 3;
  m = getDigits(zDate, 2);
  if( m<0 || m>59 ) return 1;
  zDate += 2;
  if( *zDate==':' ){
    s = getDigits(&zDate[1], 2);
    if( s<0 || s>59 ) return 1;
    zDate += 3;
    if( *zDate=='.' && isdigit(zDate[1]) ){
      double rScale = 1.0/864000.0;
      zDate++;
      while( isdigit(*zDate) ){
        ms += rScale * (*zDate - '0');
        rScale *= 0.1;
        zDate++;
      }
    }
  }else{
    s = 0;
  }
  if( parseTimezone(zDate, &tz) ) return 1;
  *prJD = (h*3600.0 + (m+tz)*60.0 + s)/86400.0 + ms;
  return 0;
}

/*
** Parse dates of the form
**
**     YYYY-MM-DD HH:MM:SS
**     YYYY-MM-DD HH:MM
**     YYYY-MM-DD
**
** Write the result as a julian day number in *prJD.  Return 0
** on success and 1 if the input string is not a well-formed
** date.
*/
static int parseYyyyMmDd(const char *zDate, double *prJD){
  int Y, M, D;
  double rTime;
  int A, B, X1, X2;

  Y = getDigits(zDate, 4);
  if( Y<0 || zDate[4]!='-' ) return 1;
  zDate += 5;
  M = getDigits(zDate, 2);
  if( M<=0 || M>12 || zDate[2]!='-' ) return 1;
  zDate += 3;
  D = getDigits(zDate, 2);
  if( D<=0 || D>31 ) return 1;
  zDate += 2;
  while( isspace(*zDate) ){ zDate++; }
  if( isdigit(*zDate) ){
    if( parseHhMmSs(zDate, &rTime) ) return 1;
  }else if( *zDate==0 ){
    rTime = 0.0;
  }else{ 
    return 1;
  }

  /* The year, month, and day are now stored in Y, M, and D.  Convert
  ** these into the Julian Day number.  See Meeus page 61.
  */
  if( M<=2 ){
    Y--;
    M += 12;
  }
  A = Y/100;
  B = 2 - A + (A/4);
  X1 = 365.25*(Y+4716);
  X2 = 30.6001*(M+1);
  *prJD = X1 + X2 + D + B - 1524.5 + rTime;
  return 0;
}

/*
** Attempt to parse the given string into a Julian Day Number.  Return
** the number of errors.
**
** The following are acceptable forms for the input string:
**
**      YYYY-MM-DD HH:MM:SS.FFF  +/-HH:MM
**      DDDD.DD 
**      now
**
** In the first form, the +/-HH:MM is always optional.  The fractional
** seconds extension (the ".FFF") is optional.  The seconds portion
** (":SS.FFF") is option.  The year and date can be omitted as long
** as there is a time string.  The time string can be omitted as long
** as there is a year and date.
**
** If the bRelative flag is set and the format is HH:MM or HH:MM:SS then
** make the result is relative to midnight instead of noon.  In other words,
** if bRelative is true, "00:00:00" parses to 0.0 but if bRelative is
** false, "00:00:00" parses to 0.5.
*/
static int parseDateOrTime(const char *zDate, int bRelative, double *prJD){
  int i;
  for(i=0; isdigit(zDate[i]); i++){}
  if( i==4 && zDate[i]=='-' ){
    return parseYyyyMmDd(zDate, prJD);
  }else if( i==2 && zDate[i]==':' ){
    if( parseHhMmSs(zDate, prJD) ) return 1;
    if( !bRelative ) *prJD += 2451544.5;
    return 0;
  }else if( i==0 && sqliteStrICmp(zDate,"now")==0 ){
    return sqliteOsCurrentTime(prJD);
  }else if( sqliteIsNumber(zDate) ){
    *prJD = atof(zDate);
    return 0;
  }
  return 1;
}

/*
** A structure for holding date and time.
*/
typedef struct DateTime DateTime;
struct DateTime {
  double rJD;    /* The julian day number */
  int Y, M, D;   /* Year, month, and day */
  int h, m;      /* Hour and minutes */
  double s;      /* Seconds */
};

/*
** Break up a julian day number into year, month, day, hour, minute, second.
** This function assume the Gregorian calendar - even for dates prior
** to the invention of the Gregorian calendar in 1582.
**
** See Meeus page 63.
**
** If mode==1 only the year, month, and day are computed.  If mode==2
** then only the hour, minute, and second are computed.  If mode==3 then
** everything is computed.  If mode==0, this routine is a no-op.
*/
static void decomposeDate(DateTime *p, int mode){
  int Z;
  Z = p->rJD + 0.5;
  if( mode & 1 ){
    int A, B, C, D, E, X1;
    A = (Z - 1867216.25)/36524.25;
    A = Z + 1 + A - (A/4);
    B = A + 1524;
    C = (B - 122.1)/365.25;
    D = 365.25*C;
    E = (B-D)/30.6001;
    X1 = 30.6001*E;
    p->D = B - D - X1;
    p->M = E<14 ? E-1 : E-13;
    p->Y = p->M>2 ? C - 4716 : C - 4715;
  }
  if( mode & 2 ){
    int s = (p->rJD + 0.5 - Z)*86400000.0 + 0.5;
    p->s = 0.001*s;
    s = p->s;
    p->s -= s;
    p->h = s/3600;
    s -= p->h*3600;
    p->m = s/60;
    p->s += s - p->m*60;
  }
}

/*
** Check to see that all arguments are valid date strings.  If any 
** argument is not a valid date string, return 0.  If all arguments
** are valid, return 1 and write into *p->rJD the sum of the julian day
** numbers for all date strings.
**
** A "valid" date string is one that is accepted by parseDateOrTime().
**
** The mode argument is passed through to decomposeDate() in order to
** fill in the year, month, day, hour, minute, and second of the *p
** structure, if desired.
*/
static int isDate(int argc, const char **argv, DateTime *p, int mode){
  double r;
  int i;
  p->rJD = 0.0;
  for(i=0; i<argc; i++){
    if( argv[i]==0 ) return 0;
    if( parseDateOrTime(argv[i], i, &r) ) return 0;
    p->rJD += r;
  }
  decomposeDate(p, mode);
  return 1;
}


/*
** The following routines implement the various date and time functions
** of SQLite.
*/
static void juliandayFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 0) ){
    sqlite_set_result_double(context, x.rJD);
  }
}
static void timestampFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 3) ){
    char zBuf[100];
    sprintf(zBuf, "%04d-%02d-%02d %02d:%02d:%02d",x.Y, x.M, x.D, x.h, x.m,
           (int)(x.s+0.5));
    sqlite_set_result_string(context, zBuf, -1);
  }
}
static void timeFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 2) ){
    char zBuf[100];
    sprintf(zBuf, "%02d:%02d:%02d", x.h, x.m, (int)(x.s+0.5));
    sqlite_set_result_string(context, zBuf, -1);
  }
}
static void dateFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 1) ){
    char zBuf[100];
    sprintf(zBuf, "%04d-%02d-%02d", x.Y, x.M, x.D);
    sqlite_set_result_string(context, zBuf, -1);
  }
}
static void yearFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 1) ){
    sqlite_set_result_int(context, x.Y);
  }
}
static void monthFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 1) ){
    sqlite_set_result_int(context, x.M);
  }
}
static void dayofweekFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 0) ){
    int Z = x.rJD + 1.5;
    sqlite_set_result_int(context, Z % 7);
  }
}
static void dayofmonthFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 1) ){
    sqlite_set_result_int(context, x.D);
  }
}
static void secondFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 2) ){
    sqlite_set_result_double(context, x.s);
  }
}
static void minuteFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 2) ){
    sqlite_set_result_int(context, x.m);
  }
}
static void hourFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 2) ){
    sqlite_set_result_int(context, x.h);
  }
}
static void unixToJdFunc(sqlite_func *context, int argc, const char **argv){
  sqlite_set_result_double(context, atof(argv[0])/(24.0*3600.0)+2440587.5);
}
static void unixtimeFunc(sqlite_func *context, int argc, const char **argv){
  DateTime x;
  if( isDate(argc, argv, &x, 0) ){
    sqlite_set_result_double(context, (x.rJD-2440587.5)*24.0*3600.0);
  }
}

#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
/***************************************************************************/

/*
** This function registered all of the above C functions as SQL
** functions.  This should be the only routine in this file with
** external linkage.
*/
void sqliteRegisterBuiltinFunctions(sqlite *db){
  static struct {
................................................................................
    { "ifnull",     2, SQLITE_ARGS,    ifnullFunc },
    { "random",    -1, SQLITE_NUMERIC, randomFunc },
    { "like",       2, SQLITE_NUMERIC, likeFunc   },
    { "glob",       2, SQLITE_NUMERIC, globFunc   },
    { "nullif",     2, SQLITE_ARGS,    nullifFunc },
    { "sqlite_version",0,SQLITE_TEXT,  versionFunc},
    { "quote",      1, SQLITE_ARGS,    quoteFunc  },
#ifndef SQLITE_OMIT_DATETIME_FUNCS
    { "julianday", -1, SQLITE_NUMERIC, juliandayFunc   },
    { "unixtime",  -1, SQLITE_NUMERIC, unixtimeFunc    },
    { "unix_to_jd", 1, SQLITE_NUMERIC, unixToJdFunc    },
    { "timestamp", -1, SQLITE_TEXT,    timestampFunc   },
    { "time",      -1, SQLITE_TEXT,    timeFunc        },
    { "date",      -1, SQLITE_TEXT,    dateFunc        },
    { "year",      -1, SQLITE_NUMERIC, yearFunc        },
    { "month",     -1, SQLITE_NUMERIC, monthFunc       },
    { "dayofmonth",-1, SQLITE_NUMERIC, dayofmonthFunc  },
    { "dayofweek", -1, SQLITE_NUMERIC, dayofweekFunc   },
    { "hour",      -1, SQLITE_NUMERIC, hourFunc        },
    { "minute",    -1, SQLITE_NUMERIC, minuteFunc      },
    { "second",    -1, SQLITE_NUMERIC, secondFunc      },
#endif
#ifdef SQLITE_SOUNDEX
    { "soundex",    1, SQLITE_TEXT,    soundexFunc},
#endif
#ifdef SQLITE_TEST
    { "randstr",    2, SQLITE_TEXT,    randStr    },
#endif
  };
................................................................................
           last_insert_rowid, db);
  sqlite_function_type(db, "last_insert_rowid", SQLITE_NUMERIC);
  for(i=0; i<sizeof(aAggs)/sizeof(aAggs[0]); i++){
    sqlite_create_aggregate(db, aAggs[i].zName,
           aAggs[i].nArg, aAggs[i].xStep, aAggs[i].xFinalize, 0);
    sqlite_function_type(db, aAggs[i].zName, aAggs[i].dataType);
  }

}







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** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.33 2003/11/01 01:53:54 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"
#include "os.h"
................................................................................
    sqlite_set_result_string(context, p->z, strlen(p->z));
  }
  if( p && p->z && p->z!=p->zBuf ){
    sqliteFree(p->z);
  }
}































































































































































































































































































































































































/*
** This function registered all of the above C functions as SQL
** functions.  This should be the only routine in this file with
** external linkage.
*/
void sqliteRegisterBuiltinFunctions(sqlite *db){
  static struct {
................................................................................
    { "ifnull",     2, SQLITE_ARGS,    ifnullFunc },
    { "random",    -1, SQLITE_NUMERIC, randomFunc },
    { "like",       2, SQLITE_NUMERIC, likeFunc   },
    { "glob",       2, SQLITE_NUMERIC, globFunc   },
    { "nullif",     2, SQLITE_ARGS,    nullifFunc },
    { "sqlite_version",0,SQLITE_TEXT,  versionFunc},
    { "quote",      1, SQLITE_ARGS,    quoteFunc  },















#ifdef SQLITE_SOUNDEX
    { "soundex",    1, SQLITE_TEXT,    soundexFunc},
#endif
#ifdef SQLITE_TEST
    { "randstr",    2, SQLITE_TEXT,    randStr    },
#endif
  };
................................................................................
           last_insert_rowid, db);
  sqlite_function_type(db, "last_insert_rowid", SQLITE_NUMERIC);
  for(i=0; i<sizeof(aAggs)/sizeof(aAggs[0]); i++){
    sqlite_create_aggregate(db, aAggs[i].zName,
           aAggs[i].nArg, aAggs[i].xStep, aAggs[i].xFinalize, 0);
    sqlite_function_type(db, aAggs[i].zName, aAggs[i].dataType);
  }
  sqliteRegisterDateTimeFunctions(db);
}

Changes to src/sqliteInt.h.

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**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.200 2003/10/18 09:37:26 danielk1977 Exp $
*/
#include "config.h"
#include "sqlite.h"
#include "hash.h"
#include "vdbe.h"
#include "parse.h"
#include "btree.h"
................................................................................
void sqliteTokenCopy(Token*, Token*);
ExprList *sqliteExprListDup(ExprList*);
SrcList *sqliteSrcListDup(SrcList*);
IdList *sqliteIdListDup(IdList*);
Select *sqliteSelectDup(Select*);
FuncDef *sqliteFindFunction(sqlite*,const char*,int,int,int);
void sqliteRegisterBuiltinFunctions(sqlite*);

int sqliteSafetyOn(sqlite*);
int sqliteSafetyOff(sqlite*);
int sqliteSafetyCheck(sqlite*);
void sqliteChangeCookie(sqlite*, Vdbe*);
void sqliteBeginTrigger(Parse*, Token*,int,int,IdList*,SrcList*,int,Expr*,int);
void sqliteFinishTrigger(Parse*, TriggerStep*, Token*);
void sqliteDropTrigger(Parse*, SrcList*);







|







 







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**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.201 2003/11/01 01:53:54 drh Exp $
*/
#include "config.h"
#include "sqlite.h"
#include "hash.h"
#include "vdbe.h"
#include "parse.h"
#include "btree.h"
................................................................................
void sqliteTokenCopy(Token*, Token*);
ExprList *sqliteExprListDup(ExprList*);
SrcList *sqliteSrcListDup(SrcList*);
IdList *sqliteIdListDup(IdList*);
Select *sqliteSelectDup(Select*);
FuncDef *sqliteFindFunction(sqlite*,const char*,int,int,int);
void sqliteRegisterBuiltinFunctions(sqlite*);
void sqliteRegisterDateTimeFunctions(sqlite*);
int sqliteSafetyOn(sqlite*);
int sqliteSafetyOff(sqlite*);
int sqliteSafetyCheck(sqlite*);
void sqliteChangeCookie(sqlite*, Vdbe*);
void sqliteBeginTrigger(Parse*, Token*,int,int,IdList*,SrcList*,int,Expr*,int);
void sqliteFinishTrigger(Parse*, TriggerStep*, Token*);
void sqliteDropTrigger(Parse*, SrcList*);

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# 2003 October 31
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing date and time functions.
#
# $Id: date.test,v 1.1 2003/11/01 01:53:54 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

proc datetest {tnum expr result} {
  do_test date-$tnum [subst {
    execsql "SELECT coalesce($expr,'NULL')"
  }] [list $result]
}

datetest 1.1 julianday('2000-01-01') 2451544.5
datetest 1.2 julianday('1970-01-01') 2440587.5
datetest 1.3 julianday('1910-04-20') 2418781.5
datetest 1.4 julianday('1986-02-09') 2446470.5
datetest 1.5 julianday('12:00:00') 2451545
datetest 1.6 {julianday('2000-01-01 12:00:00')} 2451545
datetest 1.7 {julianday('2000-01-01 12:00')} 2451545
datetest 1.8 julianday('bogus') NULL
datetest 1.9 julianday('1999-12-31') 2451543.5
datetest 1.10 julianday('1999-12-32') NULL
datetest 1.11 julianday('1999-13-01') NULL
datetest 1.12 julianday('2003-02-31') 2452701.5
datetest 1.13 julianday('2003-03-03') 2452701.5
datetest 1.14 julianday('+2000-01-01') NULL
datetest 1.15 julianday('200-01-01') NULL
datetest 1.16 julianday('2000-1-01') NULL
datetest 1.17 julianday('2000-01-1') NULL
datetest 1.18 {julianday('2000-01-01     12:00:00')} 2451545
datetest 1.19 {julianday('2000-01-01 12:00:00.1')}   2451545.00000116
datetest 1.20 {julianday('2000-01-01 12:00:00.01')}  2451545.00000012
datetest 1.21 {julianday('2000-01-01 12:00:00.001')} 2451545.00000001
datetest 1.22 {julianday('2000-01-01 12:00:00.')} NULL
datetest 1.23 julianday(12345.6) 12345.6
datetest 1.24 {julianday('2001-01-01 12:00:00 bogus')} NULL
datetest 1.25 {julianday('2001-01-01 bogus')} NULL

datetest 2.1 datetime(0,'unixepoch') {1970-01-01 00:00:00}
datetest 2.2 datetime(946684800,'unixepoch') {2000-01-01 00:00:00}
datetest 2.3 {date('2003-10-22','weekday 0')} 2003-10-26
datetest 2.4 {date('2003-10-22','weekday 1')} 2003-10-27
datetest 2.5 {date('2003-10-22','weekday 2')} 2003-10-28
datetest 2.6 {date('2003-10-22','weekday 3')} 2003-10-22
datetest 2.7 {date('2003-10-22','weekday 4')} 2003-10-23
datetest 2.8 {date('2003-10-22','weekday 5')} 2003-10-24
datetest 2.9 {date('2003-10-22','weekday 6')} 2003-10-25
datetest 2.10 {date('2003-10-22','weekday 7')} NULL
datetest 2.11 {date('2003-10-22','weekday 5.5')} NULL
datetest 2.12 {datetime('2003-10-22 12:34','weekday 0')} {2003-10-26 00:00:00}
datetest 2.13 {datetime('2003-10-22 12:34','start of month')} \
   {2003-10-01 00:00:00}
datetest 2.14 {datetime('2003-10-22 12:34','start of year')} \
   {2003-01-01 00:00:00}
datetest 2.15 {datetime('2003-10-22 12:34','start of day')} \
   {2003-10-22 00:00:00}
datetest 2.16 time('12:34:56.43') 12:34:56
datetest 2.17 {datetime('2003-10-22 12:34','1 day')} {2003-10-23 12:34:00}
datetest 2.18 {datetime('2003-10-22 12:34','+1 day')} {2003-10-23 12:34:00}
datetest 2.19 {datetime('2003-10-22 12:34','+1.25 day')} {2003-10-23 18:34:00}
datetest 2.20 {datetime('2003-10-22 12:34','-1.0 day')} {2003-10-21 12:34:00}
datetest 2.21 {datetime('2003-10-22 12:34','1 month')} {2003-11-22 12:34:00}
datetest 2.22 {datetime('2003-10-22 12:34','11 month')} {2004-09-22 12:34:00}
datetest 2.23 {datetime('2003-10-22 12:34','-13 month')} {2002-09-22 12:34:00}
datetest 2.24 {datetime('2003-10-22 12:34','1.5 months')} {2003-12-07 12:34:00}
datetest 2.25 {datetime('2003-10-22 12:34','-5 years')} {1998-10-22 12:34:00}
datetest 2.26 {datetime('2003-10-22 12:34','+10.5 minutes')} \
  {2003-10-22 12:44:30}
datetest 2.27 {datetime('2003-10-22 12:34','-1.25 hours')} \
  {2003-10-22 11:19:00}
datetest 2.28 {datetime('2003-10-22 12:34','11.25 seconds')} \
  {2003-10-22 12:34:11}
datetest 2.29 {datetime('2003-10-22 12:24','+5 bogus')} NULL


datetest 3.1 {strftime('%d','2003-10-31 12:34:56.432')} 31
datetest 3.2 {strftime('%f','2003-10-31 12:34:56.432')} 56.432
datetest 3.3 {strftime('%H','2003-10-31 12:34:56.432')} 12
datetest 3.4 {strftime('%j','2003-10-31 12:34:56.432')} 304
datetest 3.5 {strftime('%J','2003-10-31 12:34:56.432')} 2452944.024264259
datetest 3.6 {strftime('%m','2003-10-31 12:34:56.432')} 10
datetest 3.7 {strftime('%M','2003-10-31 12:34:56.432')} 34
datetest 3.8 {strftime('%s','2003-10-31 12:34:56.432')} 1067603696
datetest 3.9 {strftime('%S','2003-10-31 12:34:56.432')} 56
datetest 3.10 {strftime('%w','2003-10-31 12:34:56.432')} 5
datetest 3.11 {strftime('%W','2003-10-31 12:34:56.432')} 44
datetest 3.12 {strftime('%Y','2003-10-31 12:34:56.432')} 2003
datetest 3.13 {strftime('%%','2003-10-31 12:34:56.432')} %
datetest 3.14 {strftime('%_','2003-10-31 12:34:56.432')} NULL
datetest 3.15 {strftime('%Y-%m-%d','2003-10-31')} 2003-10-31
proc repeat {n txt} {
  set x {} 
  while {$n>0} {
    append x $txt
    incr n -1
  }
  return $x
}
datetest 3.16 "strftime('[repeat 200 %Y]','2003-10-31')" [repeat 200 2003]
datetest 3.17 "strftime('[repeat 200 abc%m123]','2003-10-31')" \
    [repeat 200 abc10123]

set now [clock format [clock seconds] -format "%Y-%m-%d" -gmt 1]
datetest 4.1 {date('now')} $now

datetest 5.1 {datetime('1994-04-16 14:00:00 -05:00')} {1994-04-16 09:00:00}
datetest 5.2 {datetime('1994-04-16 14:00:00 +05:15')} {1994-04-16 19:15:00}
datetest 5.3 {datetime('1994-04-16 05:00:00 -08:30')} {1994-04-15 20:30:00}
datetest 5.4 {datetime('1994-04-16 14:00:00 +11:55')} {1994-04-17 01:55:00}

finish_test