Experimental change to explain query plan to identify covering indexes on expressions.

FossilOrigin-Name: 3bb03a2891e30c58b66e3665a8877a8eab4a8bac57ee153d8d31358caeaf4b7c
This commit is contained in:
dan 2024-10-11 20:36:26 +00:00
parent 4859bc9a9f
commit 14101a3c28
7 changed files with 142 additions and 44 deletions

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@ -1,5 +1,5 @@
C Update\scomments\sin\sext/misc/sqlite3_stdio.c\sto\sreflect\sthe\slatest\senhancements.\nNo\schanges\sto\scode.
D 2024-10-11T19:57:41.456
C Experimental\schange\sto\sexplain\squery\splan\sto\sidentify\scovering\sindexes\son\sexpressions.
D 2024-10-11T20:36:26.974
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@ -855,9 +855,9 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
F src/wal.c a0d42bfdef935e1389737152394d08e59e7c48697f40a9fc2e0552cb19dc731f
F src/wal.h ba252daaa94f889f4b2c17c027e823d9be47ce39da1d3799886bbd51f0490452
F src/walker.c d5006d6b005e4ea7302ad390957a8d41ed83faa177e412f89bc5600a7462a014
F src/where.c 12fe24880901997372b88fd7ca9a21457404ad35201712c02cc57978578abb10
F src/whereInt.h a5d079c346a658b7a6e9e47bb943d021e02fa1e6aed3b964ca112112a4892192
F src/wherecode.c 5172d647798134e7c92536ddffe7e530c393d79b5dedd648b88faf2646c65baf
F src/where.c 55defd94b89d6ef9eb9c9a8627a799d1f9ab6f8046c72f97956cd0171e0caa5c
F src/whereInt.h 1e36ec50392f7cc3d93d1152d4338064cd522b87156a0739388b7e273735f0ca
F src/wherecode.c 8a260111af36d827d218118e36ccb8c359f9517f2743f5fe758e51dd9ae4acc7
F src/whereexpr.c 0f93a29cabd3a338d09a1f5c6770620a1ac51ec1157f3229502a7e7767c60b6f
F src/window.c 499d48f315a09242dc68f2fac635ed27dcf6bbb0d9ab9084857898c64489e975
F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
@ -1323,9 +1323,9 @@ F test/index8.test caa097735c91dbc23d8a402f5e63a2a03c83840ba3928733ed7f9a03f8a91
F test/index9.test 2ac891806a4136ef3e91280477e23114e67575207dc331e6797fa0ed9379f997
F test/indexA.test 11d84f6995e6e5b9d8315953fb1b6d29772ee7c7803ee9112715e7e4dd3e4974
F test/indexedby.test f21eca4f7a6ffe14c8500a7ad6cd53166666c99e5ccd311842a28bc94a195fe0
F test/indexexpr1.test 24fa85a12da384dd1d56f7b24e593c51a8a54b4c5e2e8bbb9e5fdf1099427faf
F test/indexexpr1.test 928671af9d7374bb56ed4dcfbc157f4eeddb1e86ab5615ceb3ac97a713c2dd8f
F test/indexexpr2.test 1c382e81ef996d8ae8b834a74f2a9013dddf59214c32201d7c8a656d739f999a
F test/indexexpr3.test 9d893bf440937ebcc1e59c7c9c1505c40c918346a3ddde76a69078f3c733c45d
F test/indexexpr3.test 47b91bc7999805c9a34d356f672259bc49295ecc797448511cae554a309b47cd
F test/indexfault.test 98d78a8ff1f5335628b62f886a1cb7c7dac1ef6d48fa39c51ec871c87dce9811
F test/init.test 15c823093fdabbf7b531fe22cf037134d09587a7
F test/insert.test 4e3f0de67aac3c5be1f4aaedbcea11638f1b5cdc9a3115be14d19aa9db7623c6
@ -2217,8 +2217,11 @@ F vsixtest/vsixtest.tcl 6195aba1f12a5e10efc2b8c0009532167be5e301abe5b31385638080
F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
P a3e16e478b03ccc12888eb5700c2e480a446957368f4b37ed322af2f4c9cd7c4
R 1291abc09c87e338ea2cfa1281bb85ca
U drh
Z 347c97452247d4e75e184990772431fa
P 9621c3b527702b47799538e028f96945b5697752dbb56078aa7f114c72fd4e1a
R dd12fabe1565dab7ca455bbaabb2f1b1
T *branch * eqp-covering-index-on-expr
T *sym-eqp-covering-index-on-expr *
T -sym-trunk *
U dan
Z 46f8403a99a7acbc4dd09a2ad01f75a8
# Remove this line to create a well-formed Fossil manifest.

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@ -1 +1 @@
9621c3b527702b47799538e028f96945b5697752dbb56078aa7f114c72fd4e1a
3bb03a2891e30c58b66e3665a8877a8eab4a8bac57ee153d8d31358caeaf4b7c

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@ -7441,14 +7441,28 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
pOp->p2 = x;
pOp->p1 = pLevel->iIdxCur;
OpcodeRewriteTrace(db, k, pOp);
}else{
/* Unable to translate the table reference into an index
** reference. Verify that this is harmless - that the
** table being referenced really is open.
*/
}else if( pLoop->wsFlags & (WHERE_IDX_ONLY|WHERE_EXPRIDX) ){
if( pLoop->wsFlags & WHERE_IDX_ONLY ){
/* An error. pLoop is supposed to be a covering index loop,
** and yet the VM code refers to a column of the table that
** is not part of the index. */
sqlite3ErrorMsg(pParse, "internal query planner error");
pParse->rc = SQLITE_INTERNAL;
}else{
/* The WHERE_EXPRIDX flag is set by the planner when it is likely
** that pLoop is a covering index loop, but it is not possible
** to be 100% sure. In this case, any OP_Explain opcode
** corresponding to this loop describes the index as a "COVERING
** INDEX". But, pOp proves that pLoop is not actually a covering
** index loop. So clear the WHERE_EXPRIDX flag and rewrite the
** text that accompanies the OP_Explain opcode, if any. */
pLoop->wsFlags &= ~WHERE_EXPRIDX;
sqlite3WhereAddExplainText(pParse,
pLevel->addrBody-1,
pTabList,
pLevel,
pWInfo->wctrlFlags
);
}
}
}else if( pOp->opcode==OP_Rowid ){

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@ -533,9 +533,17 @@ int sqlite3WhereExplainBloomFilter(
const WhereInfo *pWInfo, /* WHERE clause */
const WhereLevel *pLevel /* Bloom filter on this level */
);
void sqlite3WhereAddExplainText(
Parse *pParse, /* Parse context */
int addr,
SrcList *pTabList, /* Table list this loop refers to */
WhereLevel *pLevel, /* Scan to write OP_Explain opcode for */
u16 wctrlFlags /* Flags passed to sqlite3WhereBegin() */
);
#else
# define sqlite3WhereExplainOneScan(u,v,w,x) 0
# define sqlite3WhereExplainBloomFilter(u,v,w) 0
# define sqlite3WhereAddExplainText(u,v,w,x,y)
#endif /* SQLITE_OMIT_EXPLAIN */
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
void sqlite3WhereAddScanStatus(

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@ -110,27 +110,24 @@ static void explainIndexRange(StrAccum *pStr, WhereLoop *pLoop){
}
/*
** This function is a no-op unless currently processing an EXPLAIN QUERY PLAN
** command, or if stmt_scanstatus_v2() stats are enabled, or if SQLITE_DEBUG
** was defined at compile-time. If it is not a no-op, a single OP_Explain
** opcode is added to the output to describe the table scan strategy in pLevel.
**
** If an OP_Explain opcode is added to the VM, its address is returned.
** Otherwise, if no OP_Explain is coded, zero is returned.
** This function sets the P4 value of an existing OP_Explain opcode to
** text describing the loop in pLevel. If the OP_Explain opcode already has
** a P4 value, it is freed before it is overwritten.
*/
int sqlite3WhereExplainOneScan(
void sqlite3WhereAddExplainText(
Parse *pParse, /* Parse context */
int addr, /* Address of OP_Explain opcode */
SrcList *pTabList, /* Table list this loop refers to */
WhereLevel *pLevel, /* Scan to write OP_Explain opcode for */
u16 wctrlFlags /* Flags passed to sqlite3WhereBegin() */
){
int ret = 0;
#if !defined(SQLITE_DEBUG)
if( sqlite3ParseToplevel(pParse)->explain==2 || IS_STMT_SCANSTATUS(pParse->db) )
#endif
{
VdbeOp *pOp = sqlite3VdbeGetOp(pParse->pVdbe, addr);
SrcItem *pItem = &pTabList->a[pLevel->iFrom];
Vdbe *v = pParse->pVdbe; /* VM being constructed */
sqlite3 *db = pParse->db; /* Database handle */
int isSearch; /* True for a SEARCH. False for SCAN. */
WhereLoop *pLoop; /* The controlling WhereLoop object */
@ -139,9 +136,10 @@ int sqlite3WhereExplainOneScan(
StrAccum str; /* EQP output string */
char zBuf[100]; /* Initial space for EQP output string */
if( db->mallocFailed ) return;
pLoop = pLevel->pWLoop;
flags = pLoop->wsFlags;
if( (flags&WHERE_MULTI_OR) || (wctrlFlags&WHERE_OR_SUBCLAUSE) ) return 0;
isSearch = (flags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
|| ((flags&WHERE_VIRTUALTABLE)==0 && (pLoop->u.btree.nEq>0))
@ -165,7 +163,7 @@ int sqlite3WhereExplainOneScan(
zFmt = "AUTOMATIC PARTIAL COVERING INDEX";
}else if( flags & WHERE_AUTO_INDEX ){
zFmt = "AUTOMATIC COVERING INDEX";
}else if( flags & WHERE_IDX_ONLY ){
}else if( flags & (WHERE_IDX_ONLY|WHERE_EXPRIDX) ){
zFmt = "COVERING INDEX %s";
}else{
zFmt = "INDEX %s";
@ -219,9 +217,46 @@ int sqlite3WhereExplainOneScan(
#endif
zMsg = sqlite3StrAccumFinish(&str);
sqlite3ExplainBreakpoint("",zMsg);
ret = sqlite3VdbeAddOp4(v, OP_Explain, sqlite3VdbeCurrentAddr(v),
pParse->addrExplain, pLoop->rRun,
zMsg, P4_DYNAMIC);
assert( pOp->opcode==OP_Explain );
assert( pOp->p4type==P4_DYNAMIC || pOp->p4.z==0 );
sqlite3DbFree(db, pOp->p4.z);
pOp->p4type = P4_DYNAMIC;
pOp->p4.z = sqlite3StrAccumFinish(&str);
}
}
/*
** This function is a no-op unless currently processing an EXPLAIN QUERY PLAN
** command, or if stmt_scanstatus_v2() stats are enabled, or if SQLITE_DEBUG
** was defined at compile-time. If it is not a no-op, a single OP_Explain
** opcode is added to the output to describe the table scan strategy in pLevel.
**
** If an OP_Explain opcode is added to the VM, its address is returned.
** Otherwise, if no OP_Explain is coded, zero is returned.
*/
int sqlite3WhereExplainOneScan(
Parse *pParse, /* Parse context */
SrcList *pTabList, /* Table list this loop refers to */
WhereLevel *pLevel, /* Scan to write OP_Explain opcode for */
u16 wctrlFlags /* Flags passed to sqlite3WhereBegin() */
){
int ret = 0;
#if !defined(SQLITE_DEBUG)
if( sqlite3ParseToplevel(pParse)->explain==2 || IS_STMT_SCANSTATUS(pParse->db) )
#endif
{
if( (pLevel->pWLoop->wsFlags & WHERE_MULTI_OR)==0
&& (wctrlFlags & WHERE_OR_SUBCLAUSE)==0
){
Vdbe *v = pParse->pVdbe;
int addr = sqlite3VdbeCurrentAddr(v);
ret = sqlite3VdbeAddOp3(
v, OP_Explain, addr, pParse->addrExplain, pLevel->pWLoop->rRun
);
sqlite3WhereAddExplainText(pParse, addr, pTabList, pLevel, wctrlFlags);
}
}
return ret;
}

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@ -49,7 +49,7 @@ do_execsql_test indexexpr1-130 {
do_execsql_test indexexpr1-130eqp {
EXPLAIN QUERY PLAN
SELECT c FROM t1 WHERE b=1 AND substr(a,2,3)='nd_' ORDER BY c;
} {/USING INDEX t1ba/}
} {/USING COVERING INDEX t1ba/}
do_execsql_test indexexpr1-140 {
SELECT rowid, substr(a,b,3), '|' FROM t1 ORDER BY 2;
@ -61,7 +61,7 @@ do_execsql_test indexexpr1-141 {
do_execsql_test indexexpr1-141eqp {
EXPLAIN QUERY PLAN
SELECT rowid FROM t1 WHERE substr(a,b,3)<='and' ORDER BY +rowid;
} {/USING INDEX t1abx/}
} {/USING COVERING INDEX t1abx/}
do_execsql_test indexexpr1-142 {
SELECT rowid FROM t1 WHERE +substr(a,b,3)<='and' ORDER BY +rowid;
} {1 2 3}
@ -73,7 +73,7 @@ do_execsql_test indexexpr1-150eqp {
EXPLAIN QUERY PLAN
SELECT rowid FROM t1 WHERE substr(a,b,3) IN ('and','l_t','xyz')
ORDER BY +rowid;
} {/USING INDEX t1abx/}
} {/USING COVERING INDEX t1abx/}
ifcapable altertable {
do_execsql_test indexexpr1-160 {
@ -99,14 +99,14 @@ do_execsql_test indexexpr1-170 {
do_execsql_test indexexpr1-170eqp {
EXPLAIN QUERY PLAN
SELECT length(a) FROM t1 ORDER BY length(a);
} {/SCAN t1 USING INDEX t1alen/}
} {/SCAN t1 USING COVERING INDEX t1alen/}
do_execsql_test indexexpr1-171 {
SELECT length(a) FROM t1 ORDER BY length(a) DESC;
} {52 38 29 27 25 20}
do_execsql_test indexexpr1-171eqp {
EXPLAIN QUERY PLAN
SELECT length(a) FROM t1 ORDER BY length(a) DESC;
} {/SCAN t1 USING INDEX t1alen/}
} {/SCAN t1 USING COVERING INDEX t1alen/}
do_execsql_test indexexpr1-200 {
DROP TABLE t1;
@ -142,7 +142,7 @@ do_execsql_test indexexpr1-230 {
do_execsql_test indexexpr1-230eqp {
EXPLAIN QUERY PLAN
SELECT c FROM t1 WHERE b=1 AND substr(a,2,3)='nd_' ORDER BY c;
} {/USING INDEX t1ba/}
} {/USING COVERING INDEX t1ba/}
do_execsql_test indexexpr1-240 {
SELECT id, substr(a,b,3), '|' FROM t1 ORDER BY 2;
@ -154,7 +154,7 @@ do_execsql_test indexexpr1-241 {
do_execsql_test indexexpr1-241eqp {
EXPLAIN QUERY PLAN
SELECT id FROM t1 WHERE substr(a,b,3)<='and' ORDER BY +id;
} {/USING INDEX t1abx/}
} {/USING COVERING INDEX t1abx/}
do_execsql_test indexexpr1-242 {
SELECT id FROM t1 WHERE +substr(a,b,3)<='and' ORDER BY +id;
} {1 2 3}
@ -166,7 +166,7 @@ do_execsql_test indexexpr1-250eqp {
EXPLAIN QUERY PLAN
SELECT id FROM t1 WHERE substr(a,b,3) IN ('and','l_t','xyz')
ORDER BY +id;
} {/USING INDEX t1abx/}
} {/USING COVERING INDEX t1abx/}
ifcapable altertable {
do_execsql_test indexexpr1-260 {
@ -238,7 +238,7 @@ do_execsql_test indexexpr1-510 {
do_execsql_test indexexpr1-510eqp {
EXPLAIN QUERY PLAN
SELECT substr(a,4,3) AS k FROM cnt, t5 WHERE k=printf('%03d',x);
} {/USING INDEX t5ax/}
} {/USING COVERING INDEX t5ax/}
# Skip-scan on an indexed expression
#
@ -547,7 +547,7 @@ do_execsql_test indexexpr1-2030 {
(3, '{"x":1}', 6, 7);
CREATE INDEX t1x ON t1(d, a, b->>'x', c);
}
do_execsql_test indexexpr1-2030 {
do_execsql_test indexexpr1-2040 {
SELECT a,
SUM(1) AS t1,
SUM(CASE WHEN b->>'x'=1 THEN 1 END) AS t2,
@ -555,7 +555,7 @@ do_execsql_test indexexpr1-2030 {
SUM(CASE WHEN b->>'x'=1 THEN c END) AS t4
FROM t1;
} {1 6 4 54 46}
do_execsql_test indexexpr1-2030 {
do_execsql_test indexexpr1-2050 {
explain query plan
SELECT a,
SUM(1) AS t1,
@ -563,7 +563,7 @@ do_execsql_test indexexpr1-2030 {
SUM(c) AS t3,
SUM(CASE WHEN b->>'x'=1 THEN c END) AS t4
FROM t1;
} {/.*SCAN t1 USING INDEX t1x.*/}
} {/.*SCAN t1 USING COVERING INDEX t1x.*/}
reset_db
do_execsql_test indexexpr1-2100 {

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@ -78,6 +78,44 @@ do_hasfunction_test 1.6 {
2 {{"y":"two"}}
}
#-------------------------------------------------------------------------
reset_db
do_execsql_test 2.0 {
CREATE TABLE t1(a, b, j);
CREATE INDEX i1 ON t1( a, json_extract(j, '$.x') );
}
do_eqp_test 2.1 {
SELECT json_extract(j, '$.x') FROM t1 WHERE a=?
} {
t1 USING COVERING INDEX i1
}
do_eqp_test 2.2 {
SELECT b, json_extract(j, '$.x') FROM t1 WHERE a=?
} {
t1 USING INDEX i1
}
do_eqp_test 2.3 {
SELECT json_insert( '{}', json_extract(j, '$.x') ) FROM t1 WHERE a=?
} {
t1 USING INDEX i1
}
do_eqp_test 2.4 {
SELECT sum( json_extract(j, '$.x') ) FROM t1 WHERE a=?
} {
t1 USING COVERING INDEX i1
}
do_eqp_test 2.5 {
SELECT json_extract(j, '$.x'), sum( json_extract(j, '$.x') ) FROM t1 WHERE a=?
} {
t1 USING INDEX i1
}
finish_test