Further minor comment corrections and enhancements in where.c.

FossilOrigin-Name: 0d68d4d018e73dcbbc08786071aac6228fca1a8c

diff --git a/manifest b/manifest
index 281b26cde26833f63609cd5a27f449014b318e49..7086a26796d39bcf1d80877cbd0e526735b17d11 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Make\sa\strivial\scomment\sfix\sin\swhere.c.
-D 2013-07-01T10:38:35.899
+C Further\sminor\scomment\scorrections\sand\senhancements\sin\swhere.c.
+D 2013-07-01T11:05:50.653
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -290,7 +290,7 @@ F src/vtab.c b05e5f1f4902461ba9f5fc49bb7eb7c3a0741a83
 F src/wal.c 7dc3966ef98b74422267e7e6e46e07ff6c6eb1b4
 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c 4fa43583d0a84b48f93b1e88f11adf2065be4e73
-F src/where.c 789d319334c44d13be7a232ccced9646e8e85748
+F src/where.c 3ea606b1282032b9cc00ee7b1bb9c1d3683f7ea1
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/aggnested.test 45c0201e28045ad38a530b5a144b73cd4aa2cfd6
@@ -1098,7 +1098,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P 60b65e5ee3828c2a814bf035b57b3e8681af9397
-R 3bd4c794e157d911cc3628c2a23029da
+P 0ffaab3b9c97f4dba0f0ca6e146c8dc2775f7b1c
+R 73899855654d4162ca36e6c20fb7ad55
 U drh
-Z aca7802d1aec7347f7fd3f712b301f29
+Z 9148660e3c1a93ae29b1da887b939490

diff --git a/manifest.uuid b/manifest.uuid
index 7dc86f81102db4560d317f27504d05f7d807b891..68d4179d707ba11116044840149478d16eecd256 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-0ffaab3b9c97f4dba0f0ca6e146c8dc2775f7b1c
\ No newline at end of file
+0d68d4d018e73dcbbc08786071aac6228fca1a8c
\ No newline at end of file

diff --git a/src/where.c b/src/where.c
index b743df72323cfac8ffbd775200f0df24ce270d75..1f1944effb0de0a7c8395672a292487859e7b1b5 100644 (file)
--- a/src/where.c
+++ b/src/where.c
@@ -4428,7 +4428,7 @@ static Bitmask columnsInIndex(Index *pIdx){
 
 
 /*
-** Add all WhereLoop objects a single table of the join were the table
+** Add all WhereLoop objects for a single table of the join were the table
 ** is idenfied by pBuilder->pNew->iTab.  That table is guaranteed to be
 ** a b-tree table, not a virtual table.
 */
@@ -4892,12 +4892,19 @@ static int whereLoopAddAll(WhereLoopBuilder *pBuilder){
 /*
 ** Examine a WherePath (with the addition of the extra WhereLoop of the 5th
 ** parameters) to see if it outputs rows in the requested ORDER BY
-** (or GROUP BY) without requiring a separate source operation.  Return:
+** (or GROUP BY) without requiring a separate sort operation.  Return:
 ** 
 **    0:  ORDER BY is not satisfied.  Sorting required
 **    1:  ORDER BY is satisfied.      Omit sorting
 **   -1:  Unknown at this time
 **
+** Note that processing for WHERE_GROUPBY and WHERE_DISTINCTBY is not as
+** strict.  With GROUP BY and DISTINCT the only requirement is that
+** equivalent rows appear immediately adjacent to one another.  GROUP BY
+** and DISTINT do not require rows to appear in any particular order as long
+** as equivelent rows are grouped together.  Thus for GROUP BY and DISTINCT
+** the pOrderBy terms can be matched in any order.  With ORDER BY, the 
+** pOrderBy terms must be matched in strict left-to-right order.
 */
 static int wherePathSatisfiesOrderBy(
   WhereInfo *pWInfo,    /* The WHERE clause */
@@ -5562,7 +5569,8 @@ static int whereShortCut(WhereLoopBuilder *pBuilder){
 **
 ** ORDER BY CLAUSE PROCESSING
 **
-** pOrderBy is a pointer to the ORDER BY clause of a SELECT statement,
+** pOrderBy is a pointer to the ORDER BY clause (or the GROUP BY clause
+** if the WHERE_GROUPBY flag is set in wctrlFlags) of a SELECT statement
 ** if there is one.  If there is no ORDER BY clause or if this routine
 ** is called from an UPDATE or DELETE statement, then pOrderBy is NULL.
 */