SQLite

  b = (unsigned char *)zRight;
  while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
  return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b];
}

/*
** The string z[] is an text representation of a real number.
** Convert this string to a double and write it into *pResult.
**
** The string z[] is length bytes in length (bytes, not characters) and
** uses the encoding enc.  The string is not necessarily zero-terminated.
**
** Return TRUE if the result is a valid real number (or integer) and FALSE
** if the string is empty or contains extraneous text.  Valid numbers
** are in one of these formats:
**
**    [+-]digits[E[+-]digits]
**    [+-]digits.[digits][E[+-]digits]
**    [+-].digits[E[+-]digits]
**
** Leading and trailing whitespace is ignored for the purpose of determining
** validity.
**
** If some prefix of the input string is a valid number, this routine
** returns FALSE but it still converts the prefix and writes the result
** into *pResult.
*/
int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
#ifndef SQLITE_OMIT_FLOATING_POINT
  int incr = (enc==SQLITE_UTF8?1:2);
  const char *zEnd = z + length;
  /* sign * significand * (10 ^ (esign * exponent)) */
  int sign = 1;    /* sign of significand */
  i64 s = 0;       /* significand */
  int d = 0;       /* adjust exponent for shifting decimal point */
  int esign = 1;   /* sign of exponent */
  int e = 0;       /* exponent */
  int eValid = 1;  /* True exponent is either not used or is well-formed */
  double result;
  int nDigits = 0;

  *pResult = 0.0;   /* Default return value, in case of an error */

  if( enc==SQLITE_UTF16BE ) z++;

  /* skip leading spaces */
  while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
  if( z>=zEnd ) return 0;




  /* get sign of significand */
  if( *z=='-' ){
    sign = -1;
    z+=incr;
  }else if( *z=='+' ){
    z+=incr;

    while( z<zEnd && sqlite3Isdigit(*z) ) z+=incr, nDigits++;
  }
  if( z>=zEnd ) goto do_atof_calc;

  /* if exponent is present */
  if( *z=='e' || *z=='E' ){
    z+=incr;
    eValid = 0;
    if( z>=zEnd ) goto do_atof_calc;
    /* get sign of exponent */
    if( *z=='-' ){
      esign = -1;
      z+=incr;
    }else if( *z=='+' ){
      z+=incr;
    }
    /* copy digits to exponent */
    while( z<zEnd && sqlite3Isdigit(*z) ){
      e = e*10 + (*z - '0');
      z+=incr;
      eValid = 1;
    }
  }

  /* skip trailing spaces */
  if( nDigits && eValid ){
    while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
  }

do_atof_calc:
  /* adjust exponent by d, and update sign */
  e = (e*esign) + d;
  if( e<0 ) {
    esign = -1;
    e *= -1;

      result = (double)s;
    }
  }

  /* store the result */
  *pResult = result;

  /* return true if number and no extra non-whitespace chracters after */
  return z>=zEnd && nDigits>0 && eValid;
#else
  return !sqlite3Atoi64(z, pResult, length, enc);
#endif /* SQLITE_OMIT_FLOATING_POINT */
}

/*
** Compare the 19-character string zNum against the text representation

  set sql [format {strftime('%%H:%%M:%%f',1237962480.%03d,'unixepoch')} $i]
  set res [format {06:28:00.%03d} $i]
  datetest 2.2c-$i $sql $res
}
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 2.4a {date('2003-10-22','weekday  1')} 2003-10-27
datetest 2.4b {date('2003-10-22','weekday  1x')} NULL
datetest 2.4c {date('2003-10-22','weekday  -1')} NULL
datetest 2.4d {date('2003-10-22','weakday  1x')} NULL
datetest 2.4e {date('2003-10-22','weekday ')} NULL
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

    INSERT INTO t1 VALUES('12.32e+4',5);
    INSERT INTO t1 VALUES('12.36E+04',6);
    INSERT INTO t1 VALUES('12.36E+',7);
    INSERT INTO t1 VALUES('+123.10000E+0003',8);
    INSERT INTO t1 VALUES('+',9);
    INSERT INTO t1 VALUES('+12347.E+02',10);
    INSERT INTO t1 VALUES('+12347E+02',11);
    INSERT INTO t1 VALUES('+.125E+04',12);
    INSERT INTO t1 VALUES('-.125E+04',13);
    INSERT INTO t1 VALUES('.125E+0',14);
    INSERT INTO t1 VALUES('.125',15);
    SELECT b FROM t1 ORDER BY a, b;
  }
} {13 14 15 12 8 5 2 1 3 6 10 11 9 4 7}
do_test index-15.3 {
  execsql {
    SELECT b FROM t1 WHERE typeof(a) IN ('integer','real') ORDER BY b;
  }
} {1 2 3 5 6 8 10 11 12 13 14 15}
integrity_check index-15.4

# The following tests - index-16.* - test that when a table definition
# includes qualifications that specify the same constraint twice only a
# single index is generated to enforce the constraint.
#
# For example: "CREATE TABLE abc( x PRIMARY KEY, UNIQUE(x) );"
#

# 2010 September 30
#
# 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. Specifically,
# it tests that ticket [3998683a16a7076e08f5585c1f4816414c8c653a] where in
# floating point values with a decimal point at the beginning or end
# of the mantissa are used.
#

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

do_test tkt-3998683a16.1 {
  db eval {
    CREATE TABLE t1(x, y REAL);
    INSERT INTO t1 VALUES(1, '1.0');
    INSERT INTO t1 VALUES(2, '.125');
    INSERT INTO t1 VALUES(3, '123.');
    INSERT INTO t1 VALUES(4, '123.e+2');
    INSERT INTO t1 VALUES(5, '.125e+3');
    INSERT INTO t1 VALUES(6, '123e4');
    INSERT INTO t1 VALUES(11, '  1.0');
    INSERT INTO t1 VALUES(12, '  .125');
    INSERT INTO t1 VALUES(13, '  123.');
    INSERT INTO t1 VALUES(14, '  123.e+2');
    INSERT INTO t1 VALUES(15, '  .125e+3');
    INSERT INTO t1 VALUES(16, '  123e4');
    INSERT INTO t1 VALUES(21, '1.0  ');
    INSERT INTO t1 VALUES(22, '.125  ');
    INSERT INTO t1 VALUES(23, '123.  ');
    INSERT INTO t1 VALUES(24, '123.e+2  ');
    INSERT INTO t1 VALUES(25, '.125e+3  ');
    INSERT INTO t1 VALUES(26, '123e4  ');
    SELECT x FROM t1 WHERE typeof(y)=='real' ORDER BY x;
  }
} {1 2 3 4 5 6 11 12 13 14 15 16 21 22 23 24 25 26}

finish_test