Separate columns in keys using nulls instead of tabs. (CVS 249)
FossilOrigin-Name: 8e2f3f751ea342372c94977ff27baaff5126009a
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 8ea3e39..a22061a 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -23,7 +23,7 @@
*************************************************************************
** Internal interface definitions for SQLite.
**
-** @(#) $Id: sqliteInt.h,v 1.49 2001/09/15 13:15:13 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.50 2001/09/15 14:43:39 drh Exp $
*/
#include "sqlite.h"
#include "vdbe.h"
@@ -50,6 +50,12 @@
typedef unsigned char u8; /* 1-byte unsigned integer */
/*
+** The maximum number of bytes of data that can be put into a single
+** row of a single table.
+*/
+#define MAX_BYTES_PER_ROW 65535
+
+/*
** If memory allocation problems are found, recompile with
**
** -DMEMORY_DEBUG=1
diff --git a/src/vdbe.c b/src/vdbe.c
index 6414dc5..6adf20e 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -41,7 +41,7 @@
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
-** $Id: vdbe.c,v 1.68 2001/09/15 13:15:13 drh Exp $
+** $Id: vdbe.c,v 1.69 2001/09/15 14:43:39 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -1803,7 +1803,7 @@
}
}
nByte += sizeof(addr)*nField;
- if( nByte>65535 ){
+ if( nByte>MAX_BYTES_PER_ROW ){
rc = SQLITE_TOOBIG;
goto abort_due_to_error;
}
@@ -1837,9 +1837,10 @@
**
** Convert the top P1 entries of the stack into a single entry suitable
** for use as the key in an index or a sort. The top P1 records are
-** concatenated with a tab character (ASCII 0x09) used as a record
-** separator. The entire concatenation is null-terminated. The
-** lowest entry in the stack is the first field and the top of the
+** converted to strings and merged. The null-terminator on each string
+** is retained and used as a separator. The entire string is also
+** null-terminated.
+** The lowest entry in the stack is the first field and the top of the
** stack becomes the last.
**
** If P2 is not zero, then the original entries remain on the stack
@@ -1866,17 +1867,21 @@
nByte += aStack[i].n;
}
}
+ if( nByte+sizeof(u32)>MAX_BYTES_PER_ROW ){
+ rc = SQLITE_TOOBIG;
+ goto abort_due_to_error;
+ }
zNewKey = sqliteMalloc( nByte );
if( zNewKey==0 ) goto no_mem;
j = 0;
for(i=p->tos-nField+1; i<=p->tos; i++){
- if( (aStack[i].flags & STK_Null)==0 ){
- memcpy(&zNewKey[j], zStack[i], aStack[i].n-1);
- j += aStack[i].n-1;
+ if( aStack[i].flags & STK_Null ){
+ zNewKey[j++] = 0;
+ }else{
+ memcpy(&zNewKey[j], zStack[i], aStack[i].n);
+ j += aStack[i].n;
}
- if( i<p->tos ) zNewKey[j++] = '\t';
}
- zNewKey[j] = 0;
if( pOp->p2==0 ) PopStack(p, nField);
VERIFY( NeedStack(p, p->tos+1); )
p->tos++;
@@ -1897,7 +1902,7 @@
** entry (the lowest on the stack) is an integer record number.
**
** The converstion of the first P1 string entries occurs just like in
-** MakeKey. Each entry is separated from the others by a tab (ASCII 0x09).
+** MakeKey. Each entry is separated from the others by a null.
** The entire concatenation is null-terminated. The lowest entry
** in the stack is the first field and the top of the stack becomes the
** last.
@@ -1921,17 +1926,21 @@
nByte += aStack[i].n;
}
}
+ if( nByte>MAX_BYTES_PER_ROW ){
+ rc = SQLITE_TOOBIG;
+ goto abort_due_to_error;
+ }
zNewKey = sqliteMalloc( nByte );
if( zNewKey==0 ) goto no_mem;
j = 0;
for(i=p->tos-nField+1; i<=p->tos; i++){
- if( (aStack[i].flags & STK_Null)==0 ){
- memcpy(&zNewKey[j], zStack[i], aStack[i].n-1);
- j += aStack[i].n-1;
+ if( aStack[i].flags & STK_Null ){
+ zNewKey[j++] = 0;
+ }else{
+ memcpy(&zNewKey[j], zStack[i], aStack[i].n);
+ j += aStack[i].n;
}
- if( i<p->tos ) zNewKey[j++] = '\t';
}
- zNewKey[j++] = 0;
Integerify(p, p->tos-nField);
memcpy(&zNewKey[j], &aStack[p->tos-nField].i, sizeof(u32));
PopStack(p, nField+1);
@@ -2581,8 +2590,10 @@
** but the key used for PutIdx and DeleteIdx should be built using
** MakeIdxKey. The difference is that MakeIdxKey adds a 4-bytes
** record number to the end of the key in order to specify a particular
-** entry in the index. MakeKey specifies zero or more entries in the
-** index that all have common values.
+** entry in the index. MakeKey omits the 4-byte record number.
+** The search that this BeginIdx instruction initiates will span all
+** entries in the index where the MakeKey generated key matches all
+** but the last four bytes of the MakeIdxKey generated key.
*/
case OP_BeginIdx: {
int i = pOp->p1;
@@ -2594,10 +2605,10 @@
if( Stringify(p, tos) ) goto no_mem;
if( pCrsr->zKey ) sqliteFree(pCrsr->zKey);
pCrsr->nKey = aStack[tos].n;
- pCrsr->zKey = sqliteMalloc( 2*(pCrsr->nKey + 1) );
+ pCrsr->zKey = sqliteMalloc( 2*pCrsr->nKey );
if( pCrsr->zKey==0 ) goto no_mem;
- pCrsr->zBuf = &pCrsr->zKey[pCrsr->nKey+1];
- strncpy(pCrsr->zKey, zStack[tos], aStack[tos].n);
+ pCrsr->zBuf = &pCrsr->zKey[pCrsr->nKey];
+ memcpy(pCrsr->zKey, zStack[tos], aStack[tos].n);
pCrsr->zKey[aStack[tos].n] = 0;
rx = sqliteBtreeMoveto(pCrsr->pCursor, zStack[tos], aStack[tos].n, &res);
pCrsr->atFirst = rx==SQLITE_OK && res>0;
@@ -2610,10 +2621,12 @@
/* Opcode: NextIdx P1 P2 *
**
** The P1 cursor points to an SQL index for which a BeginIdx operation
-** has been issued. This operation retrieves the next record number and
-** pushes that record number onto the stack. Or, if there are no more
-** record numbers for the given key, this opcode pushes nothing onto the
-** stack but instead jumps to instruction P2.
+** has been issued. This operation retrieves the next record from that
+** cursor and verifies that the key on the record matches the key that
+** was pulled from the stack by the BeginIdx instruction. If they do
+** match, then the last 4 bytes of the key on the record hold a record
+** number and that record number is extracted and pushed on the stack.
+** If the keys do not match, there is an immediate jump to instruction P2.
*/
case OP_NextIdx: {
int i = pOp->p1;
@@ -2636,7 +2649,7 @@
sqliteBtreeKeySize(pCur, &size);
if( res>0 || size!=pCrsr->nKey+sizeof(u32) ||
sqliteBtreeKey(pCur, 0, pCrsr->nKey, pCrsr->zBuf)!=pCrsr->nKey ||
- strncmp(pCrsr->zKey, pCrsr->zBuf, pCrsr->nKey)!=0
+ memcmp(pCrsr->zKey, pCrsr->zBuf, pCrsr->nKey)!=0
){
pc = pOp->p2 - 1;
POPSTACK;
@@ -3786,9 +3799,9 @@
char zBuf[100];
zBuf[0] = ' ';
zBuf[1] = (aStack[i].flags & STK_Dyn)!=0 ? 'z' : 's';
- zBuf[2] = ':';
+ zBuf[2] = '[';
k = 3;
- for(j=0; j<15 && j<aStack[i].n; j++){
+ for(j=0; j<20 && j<aStack[i].n; j++){
int c = zStack[i][j];
if( c==0 && j==aStack[i].n-1 ) break;
if( isprint(c) && !isspace(c) ){
@@ -3797,6 +3810,7 @@
zBuf[k++] = '.';
}
}
+ zBuf[k++] = ']';
zBuf[k++] = 0;
fprintf(p->trace, "%s", zBuf);
}else{