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Enhancements to the DELETE command (CVS 194)

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FossilOrigin-Name: daea156e2430762e683ff5460f9f8bb3204ae168
This commit is contained in:
drh
2001-03-20 22:05:00 +00:00
parent 8721f00485
commit 0353cedda4
12 changed files with 211 additions and 236 deletions
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105
src/vdbe.c
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@@ -41,7 +41,7 @@
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** $Id: vdbe.c,v 1.52 2001/02/19 23:23:39 drh Exp $
** $Id: vdbe.c,v 1.53 2001/03/20 22:05:00 drh Exp $
*/
#include "sqliteInt.h"
#include <unistd.h>
@@ -167,6 +167,20 @@ struct SetElem {
char zKey[1]; /* Value of this key */
};
/*
** A Keylist is a bunch of keys into a table. The keylist can
** grow without bound. The keylist stores the keys of database
** records that need to be deleted.
*/
typedef struct Keylist Keylist;
struct Keylist {
int nKey; /* Number of slots in aKey[] */
int nUsed; /* Next unwritten slot in aKey[] */
int nRead; /* Next unread slot in aKey[] */
Keylist *pNext; /* Next block of keys */
int aKey[1]; /* One or more keys. Extra space allocated as needed */
};
/*
** An instance of the virtual machine
*/
@@ -188,7 +202,7 @@ struct Vdbe {
int nCursor; /* Number of slots in aCsr[] */
Cursor *aCsr; /* On element of this array for each open cursor */
int nList; /* Number of slots in apList[] */
FILE **apList; /* An open file for each list */
Keylist **apList; /* For each Keylist */
int nSort; /* Number of slots in apSort[] */
Sorter **apSort; /* An open sorter list */
FILE *pFile; /* At most one open file handler */
@@ -685,6 +699,17 @@ static int hardNeedStack(Vdbe *p, int N){
return 0;
}
/*
** Delete a keylist
*/
static void KeylistFree(Keylist *p){
while( p ){
Keylist *pNext = p->pNext;
sqliteFree(p);
p = pNext;
}
}
/*
** Clean up the VM after execution.
**
@@ -714,10 +739,8 @@ static void Cleanup(Vdbe *p){
p->aMem = 0;
p->nMem = 0;
for(i=0; i<p->nList; i++){
if( p->apList[i] ){
p->pBe->x->CloseTempFile(p->pBe, p->apList[i]);
p->apList[i] = 0;
}
KeylistFree(p->apList[i]);
p->apList[i] = 0;
}
sqliteFree(p->apList);
p->apList = 0;
@@ -2431,10 +2454,11 @@ int sqliteVdbeExec(
/* Opcode: ListOpen P1 * *
**
** Open a file used for temporary storage of integer table keys. P1
** will server as a handle to this temporary file for future
** interactions. If another temporary file with the P1 handle is
** already opened, the prior file is closed and a new one opened
** Open a "List" structure used for temporary storage of integer
** table keys. P1
** will server as a handle to this list for future
** interactions. If another list with the P1 handle is
** already opened, the prior list is closed and a new one opened
** in its place.
*/
case OP_ListOpen: {
@@ -2442,16 +2466,13 @@ int sqliteVdbeExec(
VERIFY( if( i<0 ) goto bad_instruction; )
if( i>=p->nList ){
int j;
p->apList = sqliteRealloc( p->apList, (i+1)*sizeof(FILE*) );
p->apList = sqliteRealloc( p->apList, (i+1)*sizeof(Keylist*) );
if( p->apList==0 ){ p->nList = 0; goto no_mem; }
for(j=p->nList; j<=i; j++) p->apList[j] = 0;
p->nList = i+1;
}else if( p->apList[i] ){
pBex->CloseTempFile(pBe, p->apList[i]);
}
rc = pBex->OpenTempFile(pBe, &p->apList[i]);
if( rc!=SQLITE_OK ){
sqliteSetString(pzErrMsg, "unable to open a temporary file", 0);
KeylistFree(p->apList[i]);
p->apList[i] = 0;
}
break;
}
@@ -2459,19 +2480,26 @@ int sqliteVdbeExec(
/* Opcode: ListWrite P1 * *
**
** Write the integer on the top of the stack
** into the temporary storage file P1.
** into the temporary storage list P1.
*/
case OP_ListWrite: {
int i = pOp->p1;
VERIFY( if( i<0 ) goto bad_instruction; )
Keylist *pKeylist;
VERIFY( if( i<0 || i>=p->nList ) goto bad_instruction; )
VERIFY( if( p->tos<0 ) goto not_enough_stack; )
if( VERIFY( i<p->nList && ) p->apList[i]!=0 ){
int val;
Integerify(p, p->tos);
val = aStack[p->tos].i;
POPSTACK;
fwrite(&val, sizeof(int), 1, p->apList[i]);
pKeylist = p->apList[i];
if( pKeylist==0 || pKeylist->nUsed>=pKeylist->nKey ){
pKeylist = sqliteMalloc( sizeof(Keylist)+999*sizeof(int) );
if( pKeylist==0 ) goto no_mem;
pKeylist->nKey = 1000;
pKeylist->nRead = 0;
pKeylist->nUsed = 0;
pKeylist->pNext = p->apList[i];
p->apList[i] = pKeylist;
}
Integerify(p, p->tos);
pKeylist->aKey[pKeylist->nUsed++] = aStack[p->tos].i;
POPSTACK;
break;
}
@@ -2482,9 +2510,7 @@ int sqliteVdbeExec(
case OP_ListRewind: {
int i = pOp->p1;
VERIFY( if( i<0 ) goto bad_instruction; )
if( VERIFY( i<p->nList && ) p->apList[i]!=0 ){
rewind(p->apList[i]);
}
/* This is now a no-op */
break;
}
@@ -2497,14 +2523,24 @@ int sqliteVdbeExec(
case OP_ListRead: {
int i = pOp->p1;
int val, amt;
VERIFY(if( i<0 || i>=p->nList || p->apList[i]==0 )goto bad_instruction;)
amt = fread(&val, sizeof(int), 1, p->apList[i]);
if( amt==1 ){
Keylist *pKeylist;
VERIFY(if( i<0 || i>=p->nList ) goto bad_instruction;)
pKeylist = p->apList[i];
if( pKeylist!=0 ){
VERIFY(
if( pKeylist->nRead<0
|| pKeylist->nRead>=pKeylist->nUsed
|| pKeylist->nRead>=pKeylist->nKey ) goto bad_instruction;
)
p->tos++;
if( NeedStack(p, p->tos) ) goto no_mem;
aStack[p->tos].i = val;
aStack[p->tos].i = pKeylist->aKey[pKeylist->nRead++];
aStack[p->tos].flags = STK_Int;
zStack[p->tos] = 0;
if( pKeylist->nRead>=pKeylist->nUsed ){
p->apList[i] = pKeylist->pNext;
sqliteFree(pKeylist);
}
}else{
pc = pOp->p2 - 1;
}
@@ -2518,10 +2554,9 @@ int sqliteVdbeExec(
case OP_ListClose: {
int i = pOp->p1;
VERIFY( if( i<0 ) goto bad_instruction; )
if( VERIFY( i<p->nList && ) p->apList[i]!=0 ){
pBex->CloseTempFile(pBe, p->apList[i]);
p->apList[i] = 0;
}
VERIFY( if( i>=p->nList ) goto bad_instruction; )
KeylistFree(p->apList[i]);
p->apList[i] = 0;
break;
}