/*
** This function is responsible for invoking the collation factory callback
** or substituting a collation sequence of a different encoding when the
** requested collation sequence is not available in the desired encoding.
**
** If it is not NULL, then pColl must point to the database native encoding
** collation sequence with name zName, length nName.
**
** The return value is either the collation sequence to be used in database
** db for collation type name zName, length nName, or NULL, if no collation
** sequence can be found.
**
** See also: sqlite3LocateCollSeq(), sqlite3FindCollSeq()
*/
static CollSeq sqlite3GetCollSeq(
sqlite3 db, /* The database connection */
u8 enc, /* The desired encoding for the collating sequence */
CollSeq pColl, /* Collating sequence with native encoding, or NULL */
string zName /* Collating sequence name */
)
{
CollSeq p;
p = pColl;
if (p == null)
{
p = sqlite3FindCollSeq(db, enc, zName, 0);
}
if (p == null || p.xCmp == null)
{
/* No collation sequence of this type for this encoding is registered.
** Call the collation factory to see if it can supply us with one.
*/
callCollNeeded(db, enc, zName);
p = sqlite3FindCollSeq(db, enc, zName, 0);
}
if (p != null && p.xCmp == null && synthCollSeq(db, p) != 0)
{
p = null;
}
Debug.Assert(p == null || p.xCmp != null);
return(p);
}
/*
** Parameter zName points to a UTF-8 encoded string nName bytes long.
** Return the CollSeq* pointer for the collation sequence named zName
** for the encoding 'enc' from the database 'db'.
**
** If the entry specified is not found and 'create' is true, then create a
** new entry. Otherwise return NULL.
**
** A separate function sqlite3LocateCollSeq() is a wrapper around
** this routine. sqlite3LocateCollSeq() invokes the collation factory
** if necessary and generates an error message if the collating sequence
** cannot be found.
**
** See also: sqlite3LocateCollSeq(), sqlite3GetCollSeq()
*/
static CollSeq sqlite3FindCollSeq(
sqlite3 db,
u8 enc,
string zName,
u8 create
)
{
CollSeq[] pColl;
if (zName != null)
{
pColl = findCollSeqEntry(db, zName, create);
}
else
{
pColl = new CollSeq[enc];
pColl[enc - 1] = db.pDfltColl;
}
Debug.Assert(SQLITE_UTF8 == 1 && SQLITE_UTF16LE == 2 && SQLITE_UTF16BE == 3);
Debug.Assert(enc >= SQLITE_UTF8 && enc <= SQLITE_UTF16BE);
if (pColl != null)
{
enc -= 1; // if (pColl != null) pColl += enc - 1;
return(pColl[enc]);
}
else
{
return(null);
}
}
/*
** This routine is called on a collation sequence before it is used to
** check that it is defined. An undefined collation sequence exists when
** a database is loaded that contains references to collation sequences
** that have not been defined by sqlite3_create_collation() etc.
**
** If required, this routine calls the 'collation needed' callback to
** request a definition of the collating sequence. If this doesn't work,
** an equivalent collating sequence that uses a text encoding different
** from the main database is substituted, if one is available.
*/
static int sqlite3CheckCollSeq(Parse pParse, CollSeq pColl)
{
if (pColl != null)
{
string zName = pColl.zName;
sqlite3 db = pParse.db;
CollSeq p = sqlite3GetCollSeq(db, ENC(db), pColl, zName);
if (null == p)
{
sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
pParse.nErr++;
return(SQLITE_ERROR);
}
//
//Debug.Assert(p == pColl);
if (p != pColl) // Had to lookup appropriate sequence
{
pColl.enc = p.enc;
pColl.pUser = p.pUser;
pColl.type = p.type;
pColl.xCmp = p.xCmp;
pColl.xDel = p.xDel;
}
}
return(SQLITE_OK);
}
/*
** Locate and return an entry from the db.aCollSeq hash table. If the entry
** specified by zName and nName is not found and parameter 'create' is
** true, then create a new entry. Otherwise return NULL.
**
** Each pointer stored in the sqlite3.aCollSeq hash table contains an
** array of three CollSeq structures. The first is the collation sequence
** prefferred for UTF-8, the second UTF-16le, and the third UTF-16be.
**
** Stored immediately after the three collation sequences is a copy of
** the collation sequence name. A pointer to this string is stored in
** each collation sequence structure.
*/
static CollSeq[] findCollSeqEntry(
sqlite3 db, /* Database connection */
string zName, /* Name of the collating sequence */
int create /* Create a new entry if true */
)
{
CollSeq[] pColl;
int nName = sqlite3Strlen30(zName);
pColl = sqlite3HashFind(db.aCollSeq, zName, nName, (CollSeq[])null);
if ((null == pColl) && create != 0)
{
pColl = new CollSeq[3]; //sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
if (pColl != null)
{
CollSeq pDel = null;
pColl[0] = new CollSeq();
pColl[0].zName = zName;
pColl[0].enc = SQLITE_UTF8;
pColl[1] = new CollSeq();
pColl[1].zName = zName;
pColl[1].enc = SQLITE_UTF16LE;
pColl[2] = new CollSeq();
pColl[2].zName = zName;
pColl[2].enc = SQLITE_UTF16BE;
//memcpy(pColl[0].zName, zName, nName);
//pColl[0].zName[nName] = 0;
CollSeq[] pDelArray = sqlite3HashInsert(ref db.aCollSeq, pColl[0].zName, nName, pColl);
if (pDelArray != null)
{
pDel = pDelArray[0];
}
/* If a malloc() failure occurred in sqlite3HashInsert(), it will
** return the pColl pointer to be deleted (because it wasn't added
** to the hash table).
*/
Debug.Assert(pDel == null || pDel == pColl[0]);
if (pDel != null)
{
//// db.mallocFailed = 1;
pDel = null; //was sqlite3DbFree(db,ref pDel);
pColl = null;
}
}
}
return(pColl);
}
/*
** This routine is called if the collation factory fails to deliver a
** collation function in the best encoding but there may be other versions
** of this collation function (for other text encodings) available. Use one
** of these instead if they exist. Avoid a UTF-8 <. UTF-16 conversion if
** possible.
*/
static int synthCollSeq( sqlite3 db, CollSeq pColl )
{
CollSeq pColl2;
string z = pColl.zName;
int i;
byte[] aEnc = { SQLITE_UTF16BE, SQLITE_UTF16LE, SQLITE_UTF8 };
for ( i = 0; i < 3; i++ )
{
pColl2 = sqlite3FindCollSeq( db, aEnc[i], z, 0 );
if ( pColl2.xCmp != null )
{
pColl = pColl2.Copy(); //memcpy(pColl, pColl2, sizeof(CollSeq));
pColl.xDel = null; /* Do not copy the destructor */
return SQLITE_OK;
}
}
return SQLITE_ERROR;
}
/*
** This routine is called if the collation factory fails to deliver a
** collation function in the best encoding but there may be other versions
** of this collation function (for other text encodings) available. Use one
** of these instead if they exist. Avoid a UTF-8 <. UTF-16 conversion if
** possible.
*/
static int synthCollSeq(sqlite3 db, CollSeq pColl)
{
CollSeq pColl2;
string z = pColl.zName;
int i;
byte[] aEnc = { SQLITE_UTF16BE, SQLITE_UTF16LE, SQLITE_UTF8 };
for (i = 0; i < 3; i++)
{
pColl2 = sqlite3FindCollSeq(db, aEnc[i], z, 0);
if (pColl2.xCmp != null)
{
pColl = pColl2.Copy(); //memcpy(pColl, pColl2, sizeof(CollSeq));
pColl.xDel = null; /* Do not copy the destructor */
return(SQLITE_OK);
}
}
return(SQLITE_ERROR);
}
public ITable pZombieTab; // List of Table objects to delete after code gen
#endif
#endregion
public void CopyFrom(Expr cf)
{
op = cf.op;
affinity = cf.affinity;
flags = cf.flags;
u = cf.u;
pColl = (cf.pColl == null ? null : cf.pColl.Copy());
iTable = cf.iTable;
iColumn = cf.iColumn;
pAggInfo = (cf.pAggInfo == null ? null : cf.pAggInfo.Copy());
iAgg = cf.iAgg;
iRightJoinTable = cf.iRightJoinTable;
flags2 = cf.flags2;
pTab = (cf.pTab == null ? null : cf.pTab);
#if SQLITE_MAX_EXPR_DEPTH
nHeight = cf.nHeight;
pZombieTab = cf.pZombieTab;
#endif
pLeft = (cf.pLeft == null ? null : cf.pLeft.Copy());
pRight = (cf.pRight == null ? null : cf.pRight.Copy());
x.pList = (cf.x.pList == null ? null : cf.x.pList.Copy());
x.pSelect = (cf.x.pSelect == null ? null : cf.x.pSelect.Copy());
}
/*
** Compare the values contained by the two memory cells, returning
** negative, zero or positive if pMem1 is less than, equal to, or greater
** than pMem2. Sorting order is NULL's first, followed by numbers (integers
** and reals) sorted numerically, followed by text ordered by the collating
** sequence pColl and finally blob's ordered by memcmp().
**
** Two NULL values are considered equal by this function.
*/
private static int sqlite3MemCompare(Mem pMem1, Mem pMem2, CollSeq pColl)
{
int rc;
int f1, f2;
int combined_flags;
f1 = pMem1.flags;
f2 = pMem2.flags;
combined_flags = f1 | f2;
Debug.Assert((combined_flags & MEM_RowSet) == 0);
/* If one value is NULL, it is less than the other. If both values
** are NULL, return 0.
*/
if ((combined_flags & MEM_Null) != 0)
{
return (f2 & MEM_Null) - (f1 & MEM_Null);
}
/* If one value is a number and the other is not, the number is less.
** If both are numbers, compare as reals if one is a real, or as integers
** if both values are integers.
*/
if ((combined_flags & (MEM_Int | MEM_Real)) != 0)
{
if ((f1 & (MEM_Int | MEM_Real)) == 0)
{
return 1;
}
if ((f2 & (MEM_Int | MEM_Real)) == 0)
{
return -1;
}
if ((f1 & f2 & MEM_Int) == 0)
{
double r1, r2;
if ((f1 & MEM_Real) == 0)
{
r1 = (double)pMem1.u.i;
}
else
{
r1 = pMem1.r;
}
if ((f2 & MEM_Real) == 0)
{
r2 = (double)pMem2.u.i;
}
else
{
r2 = pMem2.r;
}
if (r1 < r2)
return -1;
if (r1 > r2)
return 1;
return 0;
}
else
{
Debug.Assert((f1 & MEM_Int) != 0);
Debug.Assert((f2 & MEM_Int) != 0);
if (pMem1.u.i < pMem2.u.i)
return -1;
if (pMem1.u.i > pMem2.u.i)
return 1;
return 0;
}
}
/* If one value is a string and the other is a blob, the string is less.
** If both are strings, compare using the collating functions.
*/
if ((combined_flags & MEM_Str) != 0)
{
if ((f1 & MEM_Str) == 0)
{
return 1;
}
if ((f2 & MEM_Str) == 0)
{
return -1;
}
Debug.Assert(pMem1.enc == pMem2.enc);
Debug.Assert(pMem1.enc == SQLITE_UTF8 ||
pMem1.enc == SQLITE_UTF16LE || pMem1.enc == SQLITE_UTF16BE);
/* The collation sequence must be defined at this point, even if
** the user deletes the collation sequence after the vdbe program is
** compiled (this was not always the case).
*/
Debug.Assert(pColl == null || pColl.xCmp != null);
if (pColl != null)
{
if (pMem1.enc == pColl.enc)
{
/* The strings are already in the correct encoding. Call the
** comparison function directly */
return pColl.xCmp(pColl.pUser, pMem1.n, pMem1.z, pMem2.n, pMem2.z);
}
else
{
string v1, v2;
int n1, n2;
Mem c1 = null;
Mem c2 = null;
c1 = sqlite3Malloc(c1);// memset( &c1, 0, sizeof( c1 ) );
c2 = sqlite3Malloc(c2);// memset( &c2, 0, sizeof( c2 ) );
sqlite3VdbeMemShallowCopy(c1, pMem1, MEM_Ephem);
sqlite3VdbeMemShallowCopy(c2, pMem2, MEM_Ephem);
v1 = sqlite3ValueText((sqlite3_value)c1, pColl.enc);
n1 = v1 == null ? 0 : c1.n;
v2 = sqlite3ValueText((sqlite3_value)c2, pColl.enc);
n2 = v2 == null ? 0 : c2.n;
rc = pColl.xCmp(pColl.pUser, n1, v1, n2, v2);
sqlite3VdbeMemRelease(c1);
sqlite3VdbeMemRelease(c2);
return rc;
}
}
/* If a NULL pointer was passed as the collate function, fall through
** to the blob case and use memcmp(). */
}
/* Both values must be blobs. Compare using memcmp(). */
if ((pMem1.flags & MEM_Blob) != 0)
if (pMem1.zBLOB != null)
rc = memcmp(pMem1.zBLOB, pMem2.zBLOB, (pMem1.n > pMem2.n) ? pMem2.n : pMem1.n);
else
rc = memcmp(pMem1.z, pMem2.zBLOB, (pMem1.n > pMem2.n) ? pMem2.n : pMem1.n);
else
rc = memcmp(pMem1.z, pMem2.z, (pMem1.n > pMem2.n) ? pMem2.n : pMem1.n);
if (rc == 0)
{
rc = pMem1.n - pMem2.n;
}
return rc;
}
/*
** Set the explicit collating sequence for an expression to the
** collating sequence supplied in the second argument.
*/
static Expr sqlite3ExprSetColl( Expr pExpr, CollSeq pColl )
{
if ( pExpr != null && pColl != null )
{
pExpr.pColl = pColl;
pExpr.flags |= EP_ExpCollate;
}
return pExpr;
}
/*
** Parameter zName points to a UTF-8 encoded string nName bytes long.
** Return the CollSeq* pointer for the collation sequence named zName
** for the encoding 'enc' from the database 'db'.
**
** If the entry specified is not found and 'create' is true, then create a
** new entry. Otherwise return NULL.
**
** A separate function sqlite3LocateCollSeq() is a wrapper around
** this routine. sqlite3LocateCollSeq() invokes the collation factory
** if necessary and generates an error message if the collating sequence
** cannot be found.
**
** See also: sqlite3LocateCollSeq(), sqlite3GetCollSeq()
*/
static CollSeq sqlite3FindCollSeq(
sqlite3 db,
u8 enc,
string zName,
u8 create
)
{
CollSeq[] pColl;
if ( zName != null )
{
pColl = findCollSeqEntry( db, zName, create );
}
else
{
pColl = new CollSeq[enc];
pColl[enc - 1] = db.pDfltColl;
}
Debug.Assert( SQLITE_UTF8 == 1 && SQLITE_UTF16LE == 2 && SQLITE_UTF16BE == 3 );
Debug.Assert( enc >= SQLITE_UTF8 && enc <= SQLITE_UTF16BE );
if ( pColl != null )
{
enc -= 1; // if (pColl != null) pColl += enc - 1;
return pColl[enc];
}
else
return null;
}
/*
** Locate and return an entry from the db.aCollSeq hash table. If the entry
** specified by zName and nName is not found and parameter 'create' is
** true, then create a new entry. Otherwise return NULL.
**
** Each pointer stored in the sqlite3.aCollSeq hash table contains an
** array of three CollSeq structures. The first is the collation sequence
** prefferred for UTF-8, the second UTF-16le, and the third UTF-16be.
**
** Stored immediately after the three collation sequences is a copy of
** the collation sequence name. A pointer to this string is stored in
** each collation sequence structure.
*/
static CollSeq[] findCollSeqEntry(
sqlite3 db, /* Database connection */
string zName, /* Name of the collating sequence */
int create /* Create a new entry if true */
)
{
CollSeq[] pColl;
int nName = sqlite3Strlen30( zName );
pColl = sqlite3HashFind( db.aCollSeq, zName, nName, (CollSeq[])null );
if ( ( null == pColl ) && create != 0 )
{
pColl = new CollSeq[3]; //sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
if ( pColl != null )
{
CollSeq pDel = null;
pColl[0] = new CollSeq();
pColl[0].zName = zName;
pColl[0].enc = SQLITE_UTF8;
pColl[1] = new CollSeq();
pColl[1].zName = zName;
pColl[1].enc = SQLITE_UTF16LE;
pColl[2] = new CollSeq();
pColl[2].zName = zName;
pColl[2].enc = SQLITE_UTF16BE;
//memcpy(pColl[0].zName, zName, nName);
//pColl[0].zName[nName] = 0;
CollSeq[] pDelArray = sqlite3HashInsert( ref db.aCollSeq, pColl[0].zName, nName, pColl );
if ( pDelArray != null )
pDel = pDelArray[0];
/* If a malloc() failure occurred in sqlite3HashInsert(), it will
** return the pColl pointer to be deleted (because it wasn't added
** to the hash table).
*/
Debug.Assert( pDel == null || pDel == pColl[0] );
if ( pDel != null )
{
//// db.mallocFailed = 1;
pDel = null; //was sqlite3DbFree(db,ref pDel);
pColl = null;
}
}
}
return pColl;
}
/*
** This routine is called on a collation sequence before it is used to
** check that it is defined. An undefined collation sequence exists when
** a database is loaded that contains references to collation sequences
** that have not been defined by sqlite3_create_collation() etc.
**
** If required, this routine calls the 'collation needed' callback to
** request a definition of the collating sequence. If this doesn't work,
** an equivalent collating sequence that uses a text encoding different
** from the main database is substituted, if one is available.
*/
static int sqlite3CheckCollSeq( Parse pParse, CollSeq pColl )
{
if ( pColl != null )
{
string zName = pColl.zName;
sqlite3 db = pParse.db;
CollSeq p = sqlite3GetCollSeq( db, ENC( db ), pColl, zName );
if ( null == p )
{
sqlite3ErrorMsg( pParse, "no such collation sequence: %s", zName );
pParse.nErr++;
return SQLITE_ERROR;
}
//
//Debug.Assert(p == pColl);
if ( p != pColl ) // Had to lookup appropriate sequence
{
pColl.enc = p.enc;
pColl.pUser = p.pUser;
pColl.type = p.type;
pColl.xCmp = p.xCmp;
pColl.xDel = p.xDel;
}
}
return SQLITE_OK;
}
/*
** This function is responsible for invoking the collation factory callback
** or substituting a collation sequence of a different encoding when the
** requested collation sequence is not available in the desired encoding.
**
** If it is not NULL, then pColl must point to the database native encoding
** collation sequence with name zName, length nName.
**
** The return value is either the collation sequence to be used in database
** db for collation type name zName, length nName, or NULL, if no collation
** sequence can be found.
**
** See also: sqlite3LocateCollSeq(), sqlite3FindCollSeq()
*/
static CollSeq sqlite3GetCollSeq(
sqlite3 db, /* The database connection */
u8 enc, /* The desired encoding for the collating sequence */
CollSeq pColl, /* Collating sequence with native encoding, or NULL */
string zName /* Collating sequence name */
)
{
CollSeq p;
p = pColl;
if ( p == null )
{
p = sqlite3FindCollSeq( db, enc, zName, 0 );
}
if ( p == null || p.xCmp == null )
{
/* No collation sequence of this type for this encoding is registered.
** Call the collation factory to see if it can supply us with one.
*/
callCollNeeded( db, enc, zName );
p = sqlite3FindCollSeq( db, enc, zName, 0 );
}
if ( p != null && p.xCmp == null && synthCollSeq( db, p ) != 0 )
{
p = null;
}
Debug.Assert( p == null || p.xCmp != null );
return p;
}
//CollSeq
static int sqlite3VdbeAddOp4( Vdbe p, int op, int p1, int p2, int p3, CollSeq pP4, int p4type )
{
union_p4 _p4 = new union_p4();
_p4.pColl = pP4;
int addr = sqlite3VdbeAddOp3( p, op, p1, p2, p3 );
sqlite3VdbeChangeP4( p, addr, _p4, p4type );
return addr;
}
/*
** Change the value of the P4 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
**
** If n>=0 then the P4 operand is dynamic, meaning that a copy of
** the string is made into memory obtained from sqlite3Malloc().
** A value of n==0 means copy bytes of zP4 up to and including the
** first null byte. If n>0 then copy n+1 bytes of zP4.
**
** If n==P4_KEYINFO it means that zP4 is a pointer to a KeyInfo structure.
** A copy is made of the KeyInfo structure into memory obtained from
** sqlite3Malloc, to be freed when the Vdbe is finalized.
** n==P4_KEYINFO_HANDOFF indicates that zP4 points to a KeyInfo structure
** stored in memory that the caller has obtained from sqlite3Malloc. The
** caller should not free the allocation, it will be freed when the Vdbe is
** finalized.
**
** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
** to a string or structure that is guaranteed to exist for the lifetime of
** the Vdbe. In these cases we can just copy the pointer.
**
** If addr<0 then change P4 on the most recently inserted instruction.
*/
//P4_COLLSEQ
static void sqlite3VdbeChangeP4( Vdbe p, int addr, CollSeq pColl, int n )
{
union_p4 _p4 = new union_p4();
_p4.pColl = pColl;
sqlite3VdbeChangeP4( p, addr, _p4, n );
}
static void AnalyzeOneTable(Parse parse, Table table, Index onlyIdx, int statCurId, int memId)
{
Context ctx = parse.Ctx; // Database handle
int i; // Loop counter
int regTabname = memId++; // Register containing table name
int regIdxname = memId++; // Register containing index name
int regSampleno = memId++; // Register containing next sample number
int regCol = memId++; // Content of a column analyzed table
int regRec = memId++; // Register holding completed record
int regTemp = memId++; // Temporary use register
int regRowid = memId++; // Rowid for the inserted record
Vdbe v = parse.GetVdbe(); // The virtual machine being built up
if (v == null || C._NEVER(table == null))
{
return;
}
// Do not gather statistics on views or virtual tables or system tables
if (table.Id == 0 || table.Name.StartsWith("sqlite_", StringComparison.OrdinalIgnoreCase))
{
return;
}
Debug.Assert(Btree.HoldsAllMutexes(ctx));
int db = sqlite3SchemaToIndex(ctx, table.Schema); // Index of database containing pTab
Debug.Assert(db >= 0);
Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
#if !OMIT_AUTHORIZATION
if (Auth.Check(parse, AUTH.ANALYZE, table.Name, 0, ctx.DBs[db].Name))
{
return;
}
#endif
// Establish a read-lock on the table at the shared-cache level.
sqlite3TableLock(parse, db, table.Id, 0, table.Name);
int zeroRows = -1; // Jump from here if number of rows is zero
int idxCurId = parse.Tabs++; // Cursor open on index being analyzed
v.AddOp4(OP.String8, 0, regTabname, 0, table.Name, 0);
for (Index idx = table.Index; idx != null; idx = idx.Next) // An index to being analyzed
{
if (onlyIdx != null && onlyIdx != idx)
{
continue;
}
v.NoopComment("Begin analysis of %s", idx.Name);
int cols = idx.Columns.length;
int[] chngAddrs = C._tagalloc <int>(ctx, cols); // Array of jump instruction addresses
if (chngAddrs == null)
{
continue;
}
KeyInfo key = sqlite3IndexKeyinfo(parse, idx);
if (memId + 1 + (cols * 2) > parse.Mems)
{
parse.Mems = memId + 1 + (cols * 2);
}
// Open a cursor to the index to be analyzed.
Debug.Assert(db == sqlite3SchemaToIndex(ctx, idx.Schema));
v.AddOp4(OP.OpenRead, idxCurId, idx.Id, db, key, Vdbe.P4T.KEYINFO_HANDOFF);
v.VdbeComment("%s", idx.Name);
// Populate the registers containing the index names.
v.AddOp4(OP.String8, 0, regIdxname, 0, idx.Name, 0);
#if ENABLE_STAT3
bool once = false; // One-time initialization
if (once)
{
once = false;
sqlite3OpenTable(parse, tabCurId, db, table, OP.OpenRead);
}
v.AddOp2(OP.Count, idxCurId, regCount);
v.AddOp2(OP.Integer, STAT3_SAMPLES, regTemp1);
v.AddOp2(OP.Integer, 0, regNumEq);
v.AddOp2(OP.Integer, 0, regNumLt);
v.AddOp2(OP.Integer, -1, regNumDLt);
v.AddOp3(OP.Null, 0, regSample, regAccum);
v.AddOp4(OP.Function, 1, regCount, regAccum, (object)_stat3InitFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(2);
#endif
// The block of memory cells initialized here is used as follows.
//
// iMem:
// The total number of rows in the table.
//
// iMem+1 .. iMem+nCol:
// Number of distinct entries in index considering the left-most N columns only, where N is between 1 and nCol,
// inclusive.
//
// iMem+nCol+1 .. Mem+2*nCol:
// Previous value of indexed columns, from left to right.
//
// Cells iMem through iMem+nCol are initialized to 0. The others are initialized to contain an SQL NULL.
for (i = 0; i <= cols; i++)
{
v.AddOp2(OP.Integer, 0, memId + i);
}
for (i = 0; i < cols; i++)
{
v.AddOp2(OP.Null, 0, memId + cols + i + 1);
}
// Start the analysis loop. This loop runs through all the entries in the index b-tree.
int endOfLoop = v.MakeLabel(); // The end of the loop
v.AddOp2(OP.Rewind, idxCurId, endOfLoop);
int topOfLoop = v.CurrentAddr(); // The top of the loop
v.AddOp2(OP.AddImm, memId, 1);
int addrIfNot = 0; // address of OP_IfNot
for (i = 0; i < cols; i++)
{
v.AddOp3(OP.Column, idxCurId, i, regCol);
if (i == 0) // Always record the very first row
{
addrIfNot = v.AddOp1(OP.IfNot, memId + 1);
}
Debug.Assert(idx.CollNames != null && idx.CollNames[i] != null);
CollSeq coll = sqlite3LocateCollSeq(parse, idx.CollNames[i]);
chngAddrs[i] = v.AddOp4(OP.Ne, regCol, 0, memId + cols + i + 1, coll, Vdbe.P4T.COLLSEQ);
v.ChangeP5(SQLITE_NULLEQ);
v.VdbeComment("jump if column %d changed", i);
#if ENABLE_STAT3
if (i == 0)
{
v.AddOp2(OP.AddImm, regNumEq, 1);
v.VdbeComment("incr repeat count");
}
#endif
}
v.AddOp2(OP.Goto, 0, endOfLoop);
for (i = 0; i < cols; i++)
{
v.JumpHere(chngAddrs[i]); // Set jump dest for the OP_Ne
if (i == 0)
{
v.JumpHere(addrIfNot); // Jump dest for OP_IfNot
#if ENABLE_STAT3
v.AddOp4(OP.Function, 1, regNumEq, regTemp2, (object)Stat3PushFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(5);
v.AddOp3(OP.Column, idxCurId, idx.Columns.length, regRowid);
v.AddOp3(OP.Add, regNumEq, regNumLt, regNumLt);
v.AddOp2(OP.AddImm, regNumDLt, 1);
v.AddOp2(OP.Integer, 1, regNumEq);
#endif
}
v.AddOp2(OP.AddImm, memId + i + 1, 1);
v.AddOp3(OP.Column, idxCurId, i, memId + cols + i + 1);
}
C._tagfree(ctx, chngAddrs);
// Always jump here after updating the iMem+1...iMem+1+nCol counters
v.ResolveLabel(endOfLoop);
v.AddOp2(OP.Next, idxCurId, topOfLoop);
v.AddOp1(OP.Close, idxCurId);
#if ENABLE_STAT3
v.AddOp4(OP.Function, 1, regNumEq, regTemp2, (object)Stat3PushFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(5);
v.AddOp2(OP.Integer, -1, regLoop);
int shortJump = v.AddOp2(OP_AddImm, regLoop, 1); // Instruction address
v.AddOp4(OP.Function, 1, regAccum, regTemp1, (object)Stat3GetFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(2);
v.AddOp1(OP.IsNull, regTemp1);
v.AddOp3(OP.NotExists, tabCurId, shortJump, regTemp1);
v.AddOp3(OP.Column, tabCurId, idx->Columns[0], regSample);
sqlite3ColumnDefault(v, table, idx->Columns[0], regSample);
v.AddOp4(OP.Function, 1, regAccum, regNumEq, (object)Stat3GetFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(3);
v.AddOp4(OP.Function, 1, regAccum, regNumLt, (object)Stat3GetFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(4);
v.AddOp4(OP.Function, 1, regAccum, regNumDLt, (object)Stat3GetFuncdef, Vdbe.P4T.FUNCDEF);
v.ChangeP5(5);
v.AddOp4(OP.MakeRecord, regTabname, 6, regRec, "bbbbbb", 0);
v.AddOp2(OP.NewRowid, statCurId + 1, regNewRowid);
v.AddOp3(OP.Insert, statCurId + 1, regRec, regNewRowid);
v.AddOp2(OP.Goto, 0, shortJump);
v.JumpHere(shortJump + 2);
#endif
// Store the results in sqlite_stat1.
//
// The result is a single row of the sqlite_stat1 table. The first two columns are the names of the table and index. The third column
// is a string composed of a list of integer statistics about the index. The first integer in the list is the total number of entries
// in the index. There is one additional integer in the list for each column of the table. This additional integer is a guess of how many
// rows of the table the index will select. If D is the count of distinct values and K is the total number of rows, then the integer is computed
// as:
// I = (K+D-1)/D
// If K==0 then no entry is made into the sqlite_stat1 table.
// If K>0 then it is always the case the D>0 so division by zero is never possible.
v.AddOp2(OP_SCopy, memId, regStat1);
if (zeroRows < 0)
{
zeroRows = v.AddOp1(OP.IfNot, memId);
}
for (i = 0; i < cols; i++)
{
v.AddOp4(OP.String8, 0, regTemp, 0, " ", 0);
v.AddOp3(OP.Concat, regTemp, regStat1, regStat1);
v.AddOp3(OP.Add, memId, memId + i + 1, regTemp);
v.AddOp2(OP.AddImm, regTemp, -1);
v.AddOp3(OP.Divide, memId + i + 1, regTemp, regTemp);
v.AddOp1(OP.ToInt, regTemp);
v.AddOp3(OP.Concat, regTemp, regStat1, regStat1);
}
v.AddOp4(OP.MakeRecord, regTabname, 3, regRec, "aaa", 0);
v.AddOp2(OP.NewRowid, statCurId, regNewRowid);
v.AddOp3(OP.Insert, statCurId, regRec, regNewRowid);
v.ChangeP5(OPFLAG_APPEND);
}
// If the table has no indices, create a single sqlite_stat1 entry containing NULL as the index name and the row count as the content.
if (table.Index == null)
{
v.AddOp3(OP.OpenRead, idxCurId, table->Id, db);
v.VdbeComment("%s", table->Name);
v.AddOp2(OP.Count, idxCurId, regStat1);
v.AddOp1(OP.Close, idxCurId);
zeroRows = v.AddOp1(OP.IfNot, regStat1);
}
else
{
v.JumpHere(zeroRows);
zeroRows = v.AddOp0(OP_Goto);
}
v.AddOp2(OP.Null, 0, regIdxname);
v.AddOp4(OP.MakeRecord, regTabname, 3, regRec, "aaa", 0);
v.AddOp2(OP.NewRowid, statCurId, regNewRowid);
v.AddOp3(OP.Insert, statCurId, regRec, regNewRowid);
v.ChangeP5(OPFLAG_APPEND);
if (parse.Mems < regRec)
{
parse.Mems = regRec;
}
v.JumpHere(zeroRows);
}