Make sure the estimated row count for ephemeral tables is initialized so that

automatic indices can be used on those tables.

FossilOrigin-Name: d30f7b2deffdba373a2e0988f433c631c790a7b5

manifest

@@ -1,5 +1,8 @@
-C Fix\ssome\ssegfaults\sthat\scould\soccur\sin\sobscure\scircumstances\swhere\serror\smessages\scontained\scharacters\sthat\scould\sbe\smistaken\sfor\sprintf\sformat\sspecifiers.
-D 2010-10-21T15:12:44
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA1
+
+C Make\ssure\sthe\sestimated\srow\scount\sfor\sephemeral\stables\sis\sinitialized\sso\sthat\nautomatic\sindices\scan\sbe\sused\son\sthose\stables.
+D 2010-10-21T22:58:25
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 2c8cefd962eca0147132c7cf9eaa4bb24c656f3f
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -173,7 +176,7 @@ F src/printf.c 8ae5082dd38a1b5456030c3755ec3a392cd51506
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
 F src/resolve.c 1c0f32b64f8e3f555fe1f732f9d6f501a7f05706
 F src/rowset.c 69afa95a97c524ba6faf3805e717b5b7ae85a697
-F src/select.c 6a5c72fb0e8dc7f6133f5a9d7a747130ef0a00ea
+F src/select.c a03ec6a313ef8311f081ee478f96ae04ff691608
 F src/shell.c 8517fc1f9c59ae4007e6cc8b9af91ab231ea2056
 F src/sqlite.h.in 13f219b9ab78f22603019fd193f09d5c8913795a
 F src/sqlite3ext.h c90bd5507099f62043832d73f6425d8d5c5da754
@@ -262,7 +265,7 @@ F test/auth.test 26cc6f219580191539bf335abe03e55e49310846
 F test/auth2.test 270baddc8b9c273682760cffba6739d907bd2882
 F test/auth3.test a4755e6a2a2fea547ffe63c874eb569e60a28eb5
 F test/autoinc.test 85ef3180a737e6580086a018c09c6f1a52759b46
-F test/autoindex1.test 7df441bf0e7a88644eb80993339dbf1db3a12c68
+F test/autoindex1.test 744ad86deb6d323236dad23364fbd6465bddb7cd
 F test/autovacuum.test bb7c0885e6f8f1d633045de48f2b66082162766d
 F test/autovacuum_ioerr2.test 598b0663074d3673a9c1bc9a16e80971313bafe6
 F test/avtrans.test 0252654f4295ddda3b2cce0e894812259e655a85
@@ -873,7 +876,14 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 2c3c4ba035e548e97101142692133cf685da16bc
-R 18a7b139ced85b4a9a48c95f0f44b0f9
-U dan
-Z ed59bb88307b21a6af9f1327c9400518
+P f91471e7234db490f97298b1ccb8d6c7fc45b089
+R 4d8246ae58093be6315b04c48bfab4bb
+U drh
+Z aea84f4f863865a8d59d0384e4d2a41c
+-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v1.4.6 (GNU/Linux)
+
+iD8DBQFMwMWVoxKgR168RlERAhouAKCN7hcg9Q/00nAYD194ZTr73s9vcQCcCAs+
+QaWdxMwZcfCGWAw0Hk8qif8=
+=89cr
+-----END PGP SIGNATURE-----

manifest.uuid

@@ -1 +1 @@
-f91471e7234db490f97298b1ccb8d6c7fc45b089
+d30f7b2deffdba373a2e0988f433c631c790a7b5

src/select.c

@@ -1296,6 +1296,7 @@ Table *sqlite3ResultSetOfSelect(Parse *pParse, Select *pSelect){
   assert( db->lookaside.bEnabled==0 );
   pTab->nRef = 1;
   pTab->zName = 0;
+  pTab->nRowEst = 1000000;
   selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
   selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
   pTab->iPKey = -1;
@@ -3095,6 +3096,7 @@ static int selectExpander(Walker *pWalker, Select *p){
       while( pSel->pPrior ){ pSel = pSel->pPrior; }
       selectColumnsFromExprList(pParse, pSel->pEList, &pTab->nCol, &pTab->aCol);
       pTab->iPKey = -1;
+      pTab->nRowEst = 1000000;
       pTab->tabFlags |= TF_Ephemeral;
 #endif
     }else{

test/autoindex1.test

@@ -164,6 +164,77 @@ do_test autoindex1-502 {
        AND t501.a IN (SELECT x FROM t502 WHERE y=t501.b);
   }
 } {0 0 {TABLE t501 USING PRIMARY KEY} 0 0 {TABLE t502}}
-    
+
+
+# The following code checks a performance regression reported on the
+# mailing list on 2010-10-19.  The problem is that the nRowEst field
+# of ephermeral tables was not being initialized correctly and so no
+# automatic index was being created for the emphemeral table when it was
+# used as part of a join.
+#
+do_test autoindex1-600 {
+  db eval {
+    CREATE TABLE flock_owner(
+      owner_rec_id INTEGER CONSTRAINT flock_owner_key PRIMARY KEY,
+      flock_no VARCHAR(6) NOT NULL REFERENCES flock (flock_no),
+      owner_person_id INTEGER NOT NULL REFERENCES person (person_id),
+      owner_change_date TEXT, last_changed TEXT NOT NULL,
+      CONSTRAINT fo_owner_date UNIQUE (flock_no, owner_change_date)
+    );
+    CREATE TABLE sheep (
+      Sheep_No char(7) NOT NULL,
+      Date_of_Birth char(8),
+      Sort_DoB text,
+      Flock_Book_Vol char(2),
+      Breeder_No char(6),
+      Breeder_Person integer,
+      Originating_Flock char(6),
+      Registering_Flock char(6),
+      Tag_Prefix char(9),
+      Tag_No char(15),
+      Sort_Tag_No integer,
+      Breeders_Temp_Tag char(15),
+      Sex char(1),
+      Sheep_Name char(32),
+      Sire_No char(7),
+      Dam_No char(7),
+      Register_Code char(1),
+      Colour char(48),
+      Colour_Code char(2),
+      Pattern_Code char(8),
+      Horns char(1),
+      Litter_Size char(1),
+      Coeff_of_Inbreeding real,
+      Date_of_Registration text,
+      Date_Last_Changed text,
+      UNIQUE(Sheep_No));
+    CREATE INDEX fo_flock_no_index  
+                ON flock_owner (flock_no);
+    CREATE INDEX fo_owner_change_date_index  
+                ON flock_owner (owner_change_date);
+    CREATE INDEX fo_owner_person_id_index  
+                ON flock_owner (owner_person_id);
+    CREATE INDEX sheep_org_flock_index  
+             ON sheep (originating_flock);
+    CREATE INDEX sheep_reg_flock_index  
+             ON sheep (registering_flock);
+    EXPLAIN QUERY PLAN
+    SELECT x.sheep_no, x.registering_flock, x.date_of_registration
+     FROM sheep x LEFT JOIN
+         (SELECT s.sheep_no, prev.flock_no, prev.owner_person_id,
+         s.date_of_registration, prev.owner_change_date
+         FROM sheep s JOIN flock_owner prev ON s.registering_flock =
+     prev.flock_no
+         AND (prev.owner_change_date <= s.date_of_registration || ' 00:00:00')
+         WHERE NOT EXISTS
+             (SELECT 'x' FROM flock_owner later
+             WHERE prev.flock_no = later.flock_no
+             AND later.owner_change_date > prev.owner_change_date
+             AND later.owner_change_date <= s.date_of_registration||' 00:00:00')
+         ) y ON x.sheep_no = y.sheep_no
+     WHERE y.sheep_no IS NULL
+     ORDER BY x.registering_flock;
+  }
+} {0 0 {TABLE sheep AS s} 1 1 {TABLE flock_owner AS prev WITH INDEX sqlite_autoindex_flock_owner_1} 0 0 {TABLE flock_owner AS later WITH INDEX sqlite_autoindex_flock_owner_1} 0 0 {TABLE sheep AS x WITH INDEX sheep_reg_flock_index ORDER BY} 1 1 {TABLE  AS y WITH AUTOMATIC INDEX}}
 
 finish_test