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All the code is now in place for SQLite to distinguish between NUMERIC and

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TEXT datatypes.  Still need to turn on the new code and test it. (CVS 659)

FossilOrigin-Name: b4737a16c997a6c139d616211fb6bc4b0fae181c
This commit is contained in:
drh
2002-07-05 21:42:36 +00:00
parent 2f2c01e51d
commit 38640e15af
12 changed files with 213 additions and 81 deletions
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78
src/util.c
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@@ -14,7 +14,7 @@
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.46 2002/06/14 20:58:45 drh Exp $
** $Id: util.c,v 1.47 2002/07/05 21:42:37 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
@@ -705,11 +705,15 @@ int sqliteCompare(const char *atext, const char *btext){
** returns negative, zero, or positive if the first argument is less
** than, equal to, or greater than the first. (Result is a-b).
**
** Every string begins with either a "+" or "-" character. If the
** character is "-" then the return value is negated. This is done
** to implement a sort in descending order.
** Each string begins with one of the characters "+", "-", "A", "D".
** This character determines the sort order and collating sequence:
**
** For sorting purposes, pur numeric strings (strings for which the
** + Sort numerically in ascending order
** - Sort numerically in descending order
** A Sort as strings in ascending order
** D Sort as strings in descending order.
**
** For the "+" and "-" sorting, pure numeric strings (strings for which the
** isNum() function above returns TRUE) always compare less than strings
** that are not pure numerics. Within non-numeric strings, substrings
** of digits compare in numerical order. Finally, case is used only
@@ -721,6 +725,10 @@ int sqliteCompare(const char *atext, const char *btext){
** lexigraphical order. This routine does the additional processing
** to sort substrings of digits into numerical order and to use case
** only as a tie-breaker.
**
** The special rules above apply only to numeric sorting, when the
** prefix is "+" or "-". If the prefix is "A" or "D" then plain old
** "strcmp()" is used for the comparison.
*/
int sqliteSortCompare(const char *a, const char *b){
int len;
@@ -728,6 +736,7 @@ int sqliteSortCompare(const char *a, const char *b){
int isNumA, isNumB;
while( res==0 && *a && *b ){
assert( a[0]==b[0] );
if( a[1]==0 ){
res = -1;
break;
@@ -735,41 +744,46 @@ int sqliteSortCompare(const char *a, const char *b){
res = +1;
break;
}
isNumA = sqliteIsNumber(&a[1]);
isNumB = sqliteIsNumber(&b[1]);
if( isNumA ){
double rA, rB;
if( !isNumB ){
res = -1;
break;
}
rA = atof(&a[1]);
rB = atof(&b[1]);
if( rA<rB ){
res = -1;
break;
}
if( rA>rB ){
if( a[0]=='A' || a[0]=='D' ){
res = strcmp(&a[1],&b[1]);
if( res ) break;
}else{
isNumA = sqliteIsNumber(&a[1]);
isNumB = sqliteIsNumber(&b[1]);
if( isNumA ){
double rA, rB;
if( !isNumB ){
res = -1;
break;
}
rA = atof(&a[1]);
rB = atof(&b[1]);
if( rA<rB ){
res = -1;
break;
}
if( rA>rB ){
res = +1;
break;
}
}else if( isNumB ){
res = +1;
break;
}
}else if( isNumB ){
res = +1;
break;
}else{
res = sortStrCmp(&a[1],&b[1],0);
if( res==0 ){
res = sortStrCmp(&a[1],&b[1],1);
}
if( res!=0 ){
break;
}else{
res = sortStrCmp(&a[1],&b[1],0);
if( res==0 ){
res = sortStrCmp(&a[1],&b[1],1);
}
if( res!=0 ){
break;
}
}
}
len = strlen(&a[1]) + 2;
a += len;
b += len;
}
if( *a=='-' ) res = -res;
if( *a=='-' || *a=='D' ) res = -res;
return res;
}