Begin a branch that experimentally replaces sqlite_stat2 with a new table
called sqlite_stat3 that will hopefully facilitate better query
planning decisions.
FossilOrigin-Name: 52e1d7e8ddd4bb5ef3a9d00fd2d719a8a784f807
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index bcf6a59..6bb14b6 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -446,6 +446,18 @@
#define SQLITE_MAX_U32 ((((u64)1)<<32)-1)
/*
+** The datatype used to store estimates of the number of rows in a
+** table or index. This is an unsigned integer type. For 99.9% of
+** the world, a 32-bit integer is sufficient. But a 64-bit integer
+** can be used at compile-time if desired.
+*/
+#ifdef SQLITE_64BIT_STATS
+ typedef u64 tRowcnt; /* 64-bit only if requested at compile-time */
+#else
+ typedef u32 tRowcnt; /* 32-bit is the default */
+#endif
+
+/*
** Macros to determine whether the machine is big or little endian,
** evaluated at runtime.
*/
@@ -1278,7 +1290,7 @@
Column *aCol; /* Information about each column */
Index *pIndex; /* List of SQL indexes on this table. */
int tnum; /* Root BTree node for this table (see note above) */
- unsigned nRowEst; /* Estimated rows in table - from sqlite_stat1 table */
+ tRowcnt nRowEst; /* Estimated rows in table - from sqlite_stat1 table */
Select *pSelect; /* NULL for tables. Points to definition if a view. */
u16 nRef; /* Number of pointers to this Table */
u8 tabFlags; /* Mask of TF_* values */
@@ -1477,18 +1489,21 @@
char *zName; /* Name of this index */
int nColumn; /* Number of columns in the table used by this index */
int *aiColumn; /* Which columns are used by this index. 1st is 0 */
- unsigned *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
+ tRowcnt *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
Table *pTable; /* The SQL table being indexed */
int tnum; /* Page containing root of this index in database file */
u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
u8 autoIndex; /* True if is automatically created (ex: by UNIQUE) */
u8 bUnordered; /* Use this index for == or IN queries only */
+ u8 nSample; /* Number of elements in aSample[] */
char *zColAff; /* String defining the affinity of each column */
Index *pNext; /* The next index associated with the same table */
Schema *pSchema; /* Schema containing this index */
u8 *aSortOrder; /* Array of size Index.nColumn. True==DESC, False==ASC */
char **azColl; /* Array of collation sequence names for index */
- IndexSample *aSample; /* Array of SQLITE_INDEX_SAMPLES samples */
+#ifdef SQLITE_ENABLE_STAT3
+ IndexSample *aSample; /* Samples of the left-most key */
+#endif
};
/*
@@ -1498,10 +1513,13 @@
struct IndexSample {
union {
char *z; /* Value if eType is SQLITE_TEXT or SQLITE_BLOB */
- double r; /* Value if eType is SQLITE_FLOAT or SQLITE_INTEGER */
+ double r; /* Value if eType is SQLITE_FLOAT */
+ i64 i; /* Value if eType is SQLITE_INTEGER */
} u;
u8 eType; /* SQLITE_NULL, SQLITE_INTEGER ... etc. */
- u8 nByte; /* Size in byte of text or blob. */
+ u16 nByte; /* Size in byte of text or blob. */
+ tRowcnt nEq; /* Est. number of rows where the key equals this sample */
+ tRowcnt nLt; /* Est. number of rows where key is less than this sample */
};
/*
@@ -2707,6 +2725,7 @@
#endif
void sqlite3DropTable(Parse*, SrcList*, int, int);
+void sqlite3CodeDropTable(Parse*, Table*, int, int);
void sqlite3DeleteTable(sqlite3*, Table*);
#ifndef SQLITE_OMIT_AUTOINCREMENT
void sqlite3AutoincrementBegin(Parse *pParse);
@@ -2963,7 +2982,7 @@
void sqlite3ValueFree(sqlite3_value*);
sqlite3_value *sqlite3ValueNew(sqlite3 *);
char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
-#ifdef SQLITE_ENABLE_STAT2
+#ifdef SQLITE_ENABLE_STAT3
char *sqlite3Utf8to16(sqlite3 *, u8, char *, int, int *);
#endif
int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);