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Simplification to the random rowid picking logic that begins running when

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the maximum possible rowid has already been used.

FossilOrigin-Name: 1330c72e172324c68ab49e5bb2ceba985935ae01
This commit is contained in:
drh
2014-09-25 12:31:28 +00:00
parent 9fdfdc893b
commit 2c4dc635a1
4 changed files with 16 additions and 26 deletions
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22
src/vdbe.c
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@@ -4020,25 +4020,15 @@ case OP_NewRowid: { /* out2-prerelease */
** it finds one that is not previously used. */
assert( pOp->p3==0 ); /* We cannot be in random rowid mode if this is
** an AUTOINCREMENT table. */
/* on the first attempt, simply do one more than previous */
v = lastRowid;
v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
v++; /* ensure non-zero */
cnt = 0;
while( ((rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)v,
do{
sqlite3_randomness(sizeof(v), &v);
v &= (MAX_ROWID>>1);
v++;
}while( ((rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)v,
0, &res))==SQLITE_OK)
&& (res==0)
&& (++cnt<100)){
/* collision - try another random rowid */
sqlite3_randomness(sizeof(v), &v);
if( cnt<5 ){
/* try "small" random rowids for the initial attempts */
v &= 0xffffff;
}else{
v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
}
v++; /* ensure non-zero */
}
&& (++cnt<100));
if( rc==SQLITE_OK && res==0 ){
rc = SQLITE_FULL; /* IMP: R-38219-53002 */
goto abort_due_to_error;