SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.51 2002/02/28 03:04:48 drh Exp $
*/
#include "sqliteInt.h"


/*
** Construct a new expression node and return a pointer to it.  Memory
** for this node is obtained from sqliteMalloc().  The calling function

      int n = pExpr->pList ? pExpr->pList->nExpr : 0;
      int no_such_func = 0;
      int wrong_num_args = 0;
      int is_agg = 0;
      int i;
      FuncDef *pDef;

      pDef = sqliteFindFunction(pParse->db,
         pExpr->token.z, pExpr->token.n, n, 0);
      if( pDef==0 ){
        pDef = sqliteFindFunction(pParse->db,
           pExpr->token.z, pExpr->token.n, -1, 0);
        if( pDef==0 ){
          no_such_func = 1;
        }else{
          wrong_num_args = 1;

    case TK_AGG_FUNCTION: {
      sqliteVdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
      break;
    }
    case TK_FUNCTION: {
      int i;
      ExprList *pList = pExpr->pList;
      int nExpr = pList ? pList->nExpr : 0;
      FuncDef *pDef;
      pDef = sqliteFindFunction(pParse->db,
                      pExpr->token.z, pExpr->token.n, nExpr, 0);
      assert( pDef!=0 );
      for(i=0; i<nExpr; i++){
        sqliteExprCode(pParse, pList->a[i].pExpr);
      }
      sqliteVdbeAddOp(v, OP_Function, nExpr, 0);
      sqliteVdbeChangeP3(v, -1, (char*)pDef, P3_POINTER);
      break;
    }
    case TK_SELECT: {
      sqliteVdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      break;
    }

  if( p && !createFlag && p->xFunc==0 && p->xStep==0 ){
    return 0;
  }
  if( p==0 && pMaybe ){
    assert( createFlag==0 );
    return pMaybe;
  }
  if( p==0 && createFlag && (p = sqliteMalloc(sizeof(*p)))!=0 ){

    p->nArg = nArg;
    p->pNext = pFirst;
    sqliteHashInsert(&db->aFunc, zName, nName, (void*)p);
  }
  return p;
}

** 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 1.9 2002/02/28 03:04:48 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"

/*
** Implementation of the non-aggregate min() and max() functions
*/
static void minFunc(sqlite_func *context, int argc, const char **argv){
  const char *zBest; 
  int i;

  if( argc==0 ) return;
  zBest = argv[0];
  for(i=1; i<argc; i++){
    if( sqliteCompare(argv[i], zBest)<0 ){
      zBest = argv[i];
    }
  }
  sqlite_set_result_string(context, zBest, -1);
}
static void maxFunc(sqlite_func *context, int argc, const char **argv){
  const char *zBest; 
  int i;

  if( argc==0 ) return;
  zBest = argv[0];
  for(i=1; i<argc; i++){
    if( sqliteCompare(argv[i], zBest)>0 ){
      zBest = argv[i];
    }
  }
  sqlite_set_result_string(context, zBest, -1);

  p2 = atoi(argv[2]?argv[2]:0);
#ifdef SQLITE_UTF8
  for(len=0, z2=z; *z2; z2++){ if( (0xc0&*z)!=0x80 ) len++; }
#else
  len = strlen(z);
#endif
  if( p1<0 ){
    p1 += len;
  }else if( p1>0 ){
    p1--;
  }
  if( p1+p2>len ){
    p2 = len-p1;
  }
#ifdef SQLITE_UTF8

  if( p==0 ) return;
  x = argv[0] ? atof(argv[0]) : 0.0;
  p->sum += x;
}
static void sumFinalize(sqlite_func *context){
  SumCtx *p;
  p = sqlite_aggregate_context(context, sizeof(*p));

  sqlite_set_result_double(context, p ? p->sum : 0.0);

}
static void avgFinalize(sqlite_func *context){
  SumCtx *p;
  double rN;
  p = sqlite_aggregate_context(context, sizeof(*p));
  rN = sqlite_aggregate_count(context);
  if( p && rN>0.0 ){

** type to the other occurs as necessary.
** 
** Most of the code in this file is taken up by the sqliteVdbeExec()
** function which does the work of interpreting a VDBE program.
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** $Id: vdbe.c,v 1.128 2002/02/28 03:04:48 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_MoveTo or the OP_Next opcode.  The test

  if( p->s.flags & STK_Dyn ){
    sqliteFree(p->z);
  }
  if( zResult==0 ){
    p->s.flags = STK_Null;
    n = 0;
    p->z = 0;
    p->s.n = 0;
  }else{
    if( n<0 ) n = strlen(zResult);
    if( n<NBFS-1 ){
      memcpy(p->s.z, zResult, n);
      p->s.z[n] = 0;
      p->s.flags = STK_Str;
      p->z = p->s.z;
    }else{
      p->z = sqliteMalloc( n+1 );
      if( p->z ){
        memcpy(p->z, zResult, n);
        p->z[n] = 0;
      }
      p->s.flags = STK_Str | STK_Dyn;
    }
    p->s.n = n+1;
  }

  return p->z;
}
void sqlite_set_result_int(sqlite_func *p, int iResult){
  assert( !p->isStep );
  if( p->s.flags & STK_Dyn ){
    sqliteFree(p->z);
  }

** See also: AggFunc
*/
case OP_Function: {
  int n, i;
  sqlite_func ctx;

  n = pOp->p1;
  VERIFY( if( n<0 ) goto bad_instruction; )
  VERIFY( if( p->tos+1<n ) goto not_enough_stack; )
  for(i=p->tos-n+1; i<=p->tos; i++){
    if( (aStack[i].flags & STK_Null)==0 ){
      if( Stringify(p, i) ) goto no_mem;
    }
  }
  ctx.pFunc = (FuncDef*)pOp->p3;

# 2001 September 15
#
# 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 built-in functions.
#
# $Id: func.test,v 1.8 2002/02/28 03:04:48 drh Exp $

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

# Create a table to work with.
#
do_test func-0.0 {

#
do_test func-1.0 {
  execsql {SELECT length(t1) FROM tbl1 ORDER BY t1}
} {4 2 7 8 4}
do_test func-1.1 {
  set r [catch {execsql {SELECT length(*) FROM tbl1 ORDER BY t1}} msg]
  lappend r $msg
} {1 {wrong number of arguments to function length()}}
do_test func-1.2 {
  set r [catch {execsql {SELECT length(t1,5) FROM tbl1 ORDER BY t1}} msg]
  lappend r $msg
} {1 {wrong number of arguments to function length()}}
do_test func-1.3 {
  execsql {SELECT length(t1), count(*) FROM tbl1 GROUP BY length(t1)
           ORDER BY length(t1)}
} {2 1 4 2 7 1 8 1}

# Check out the substr() function
#

  execsql {
    CREATE TABLE t1(a,b,c);
    INSERT INTO t1 VALUES(1,2,3);
    INSERT INTO t1 VALUES(2,1.2345678901234,-12345.67890);
    INSERT INTO t1 VALUES(3,-2,-5);
  }
  catchsql {SELECT abs(a,b) FROM t1}
} {1 {wrong number of arguments to function abs()}}
do_test func-4.2 {
  catchsql {SELECT abs() FROM t1}
} {1 {wrong number of arguments to function abs()}}
do_test func-4.3 {
  catchsql {SELECT abs(b) FROM t1 ORDER BY a}
} {0 {2 1.2345678901234 2}}
do_test func-4.4 {
  catchsql {SELECT abs(c) FROM t1 ORDER BY a}
} {0 {3 12345.67890 5}}

do_test func-4.5 {
  catchsql {SELECT round(a,b,c) FROM t1}
} {1 {wrong number of arguments to function round()}}
do_test func-4.6 {
  catchsql {SELECT round(b,2) FROM t1 ORDER BY b}
} {0 {-2.00 1.23 2.00}}
do_test func-4.7 {
  catchsql {SELECT round(b,0) FROM t1 ORDER BY a}
} {0 {2 1 -2}}
do_test func-4.8 {
  catchsql {SELECT round(c) FROM t1 ORDER BY a}
} {0 {3 -12346 -5}}
do_test func-4.9 {
  catchsql {SELECT round(c,a) FROM t1 ORDER BY a}
} {0 {3.0 -12345.68 -5.000}}
do_test func-4.10 {
  catchsql {SELECT 'x' || round(c,a) || 'y' FROM t1 ORDER BY a}
} {0 {x3.0y x-12345.68y x-5.000y}}
do_test func-4.11 {
  catchsql {SELECT round() FROM t1 ORDER BY a}
} {1 {wrong number of arguments to function round()}}

finish_test

# 2001 September 15
#
# 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 the SELECT statement.
#
# $Id: select1.test,v 1.20 2002/02/28 03:04:48 drh Exp $

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

# Try to select on a non-existant table.
#
do_test select1-1.1 {

execsql {INSERT INTO test1 VALUES(33,44)}

# Error messges from sqliteExprCheck
#
do_test select1-2.1 {
  set v [catch {execsql {SELECT count(f1,f2) FROM test1}} msg]
  lappend v $msg
} {1 {wrong number of arguments to function count()}}
do_test select1-2.2 {
  set v [catch {execsql {SELECT count(f1) FROM test1}} msg]
  lappend v $msg
} {0 2}
do_test select1-2.3 {
  set v [catch {execsql {SELECT Count() FROM test1}} msg]
  lappend v $msg
} {0 2}
do_test select1-2.4 {
  set v [catch {execsql {SELECT COUNT(*) FROM test1}} msg]
  lappend v $msg
} {0 2}
do_test select1-2.5 {
  set v [catch {execsql {SELECT COUNT(*)+1 FROM test1}} msg]
  lappend v $msg
} {0 3}
do_test select1-2.6 {
  set v [catch {execsql {SELECT min(*) FROM test1}} msg]
  lappend v $msg
} {0 {{} {}}}
do_test select1-2.7 {
  set v [catch {execsql {SELECT Min(f1) FROM test1}} msg]
  lappend v $msg
} {0 11}
do_test select1-2.8 {
  set v [catch {execsql {SELECT MIN(f1,f2) FROM test1}} msg]
  lappend v [lsort $msg]
} {0 {11 33}}
do_test select1-2.9 {
  set v [catch {execsql {SELECT MAX(*) FROM test1}} msg]
  lappend v $msg
} {0 {{} {}}}
do_test select1-2.10 {
  set v [catch {execsql {SELECT Max(f1) FROM test1}} msg]
  lappend v $msg
} {0 33}
do_test select1-2.11 {
  set v [catch {execsql {SELECT max(f1,f2) FROM test1}} msg]
  lappend v [lsort $msg]
} {0 {22 44}}
do_test select1-2.12 {
  set v [catch {execsql {SELECT MAX(f1,f2)+1 FROM test1}} msg]
  lappend v [lsort $msg]
} {0 {23 45}}
do_test select1-2.13 {
  set v [catch {execsql {SELECT MAX(f1)+1 FROM test1}} msg]
  lappend v $msg
} {0 34}
do_test select1-2.14 {
  set v [catch {execsql {SELECT SUM(*) FROM test1}} msg]
  lappend v $msg
} {1 {wrong number of arguments to function SUM()}}
do_test select1-2.15 {
  set v [catch {execsql {SELECT Sum(f1) FROM test1}} msg]
  lappend v $msg
} {0 44}
do_test select1-2.16 {
  set v [catch {execsql {SELECT sum(f1,f2) FROM test1}} msg]
  lappend v $msg
} {1 {wrong number of arguments to function sum()}}
do_test select1-2.17 {
  set v [catch {execsql {SELECT SUM(f1)+1 FROM test1}} msg]
  lappend v $msg
} {0 45}
do_test select1-2.18 {
  set v [catch {execsql {SELECT XYZZY(f1) FROM test1}} msg]
  lappend v $msg

do_test select1-3.8 {
  set v [catch {execsql {SELECT f1 FROM test1 WHERE max(f1,f2)!=11}} msg]
  lappend v [lsort $msg]
} {0 {11 33}}
do_test select1-3.9 {
  set v [catch {execsql {SELECT f1 FROM test1 WHERE count(f1,f2)!=11}} msg]
  lappend v $msg
} {1 {wrong number of arguments to function count()}}

# ORDER BY expressions
#
do_test select1-4.1 {
  set v [catch {execsql {SELECT f1 FROM test1 ORDER BY f1}} msg]
  lappend v $msg
} {0 {11 33}}

  }
} {11 33}
do_test select1-8.4 {
  execsql {
    SELECT f1/(f1-11), min(f1/(f1-11),5), max(f1/(f1-33),6)
    FROM test1 ORDER BY f1
  }
} {{} {} 6 1.5 1.5 6}
do_test select1-8.5 {
  execsql {
    SELECT min(1,2,3), -max(1,2,3)
    FROM test1 ORDER BY f1
  }
} {1 -3 1 -3}