SQLite

Check-in [8232050190]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Add comments to the WHERE_DISTINCT_* macros. No changes to code.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 82320501904f65030622a67836ba30f412169056
User & Date: drh 2012-09-19 17:31:15.874
Context
2012-09-19
21:15
Tighter VDBE code for the WHERE_DISTINCT_ORDERED case of DISTINCT keyword handling. (check-in: 94b48064db user: drh tags: trunk)
17:31
Add comments to the WHERE_DISTINCT_* macros. No changes to code. (check-in: 8232050190 user: drh tags: trunk)
00:35
Merge the covering-index-scan optimization into trunk. (check-in: ddd5d789e7 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/sqliteInt.h.
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999


2000
2001
2002
2003
2004
2005
2006
2007
2008
** into the second half to give some continuity.
*/
struct WhereInfo {
  Parse *pParse;       /* Parsing and code generating context */
  u16 wctrlFlags;      /* Flags originally passed to sqlite3WhereBegin() */
  u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
  u8 untestedTerms;    /* Not all WHERE terms resolved by outer loop */
  u8 eDistinct;
  SrcList *pTabList;             /* List of tables in the join */
  int iTop;                      /* The very beginning of the WHERE loop */
  int iContinue;                 /* Jump here to continue with next record */
  int iBreak;                    /* Jump here to break out of the loop */
  int nLevel;                    /* Number of nested loop */
  struct WhereClause *pWC;       /* Decomposition of the WHERE clause */
  double savedNQueryLoop;        /* pParse->nQueryLoop outside the WHERE loop */
  double nRowOut;                /* Estimated number of output rows */
  WhereLevel a[1];               /* Information about each nest loop in WHERE */
};



#define WHERE_DISTINCT_UNIQUE 1
#define WHERE_DISTINCT_ORDERED 2

/*
** A NameContext defines a context in which to resolve table and column
** names.  The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList).  The named expression list may
** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
** to the table being operated on by INSERT, UPDATE, or DELETE.  The







|











>
>
|
|







1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
** into the second half to give some continuity.
*/
struct WhereInfo {
  Parse *pParse;       /* Parsing and code generating context */
  u16 wctrlFlags;      /* Flags originally passed to sqlite3WhereBegin() */
  u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
  u8 untestedTerms;    /* Not all WHERE terms resolved by outer loop */
  u8 eDistinct;                  /* One of the WHERE_DISTINCT_* values below */
  SrcList *pTabList;             /* List of tables in the join */
  int iTop;                      /* The very beginning of the WHERE loop */
  int iContinue;                 /* Jump here to continue with next record */
  int iBreak;                    /* Jump here to break out of the loop */
  int nLevel;                    /* Number of nested loop */
  struct WhereClause *pWC;       /* Decomposition of the WHERE clause */
  double savedNQueryLoop;        /* pParse->nQueryLoop outside the WHERE loop */
  double nRowOut;                /* Estimated number of output rows */
  WhereLevel a[1];               /* Information about each nest loop in WHERE */
};

/* Allowed values for WhereInfo.eDistinct */
#define WHERE_DISTINCT_NOT     0  /* May contain non-adjacent duplicates */
#define WHERE_DISTINCT_UNIQUE  1  /* No duplicates */
#define WHERE_DISTINCT_ORDERED 2  /* All duplicates are adjacent */

/*
** A NameContext defines a context in which to resolve table and column
** names.  The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList).  The named expression list may
** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
** to the table being operated on by INSERT, UPDATE, or DELETE.  The