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diff --git a/src/whereInt.h b/src/whereInt.h new file mode 100644 index 0000000..f3cc577 --- /dev/null +++ b/src/whereInt.h @@ -0,0 +1,639 @@ +/* +** 2013-11-12 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** +** This file contains structure and macro definitions for the query +** planner logic in "where.c". These definitions are broken out into +** a separate source file for easier editing. +*/ +#ifndef SQLITE_WHEREINT_H +#define SQLITE_WHEREINT_H + + +/* Forward references +*/ +typedef struct WhereClause WhereClause; +typedef struct WhereMaskSet WhereMaskSet; +typedef struct WhereOrInfo WhereOrInfo; +typedef struct WhereAndInfo WhereAndInfo; +typedef struct WhereLevel WhereLevel; +typedef struct WhereLoop WhereLoop; +typedef struct WherePath WherePath; +typedef struct WhereTerm WhereTerm; +typedef struct WhereLoopBuilder WhereLoopBuilder; +typedef struct WhereScan WhereScan; +typedef struct WhereOrCost WhereOrCost; +typedef struct WhereOrSet WhereOrSet; +typedef struct WhereMemBlock WhereMemBlock; +typedef struct WhereRightJoin WhereRightJoin; + +/* +** This object is a header on a block of allocated memory that will be +** automatically freed when its WInfo object is destructed. +*/ +struct WhereMemBlock { + WhereMemBlock *pNext; /* Next block in the chain */ + u64 sz; /* Bytes of space */ +}; + +/* +** Extra information attached to a WhereLevel that is a RIGHT JOIN. +*/ +struct WhereRightJoin { + int iMatch; /* Cursor used to determine prior matched rows */ + int regBloom; /* Bloom filter for iRJMatch */ + int regReturn; /* Return register for the interior subroutine */ + int addrSubrtn; /* Starting address for the interior subroutine */ + int endSubrtn; /* The last opcode in the interior subroutine */ +}; + +/* +** This object contains information needed to implement a single nested +** loop in WHERE clause. +** +** Contrast this object with WhereLoop. This object describes the +** implementation of the loop. WhereLoop describes the algorithm. +** This object contains a pointer to the WhereLoop algorithm as one of +** its elements. +** +** The WhereInfo object contains a single instance of this object for +** each term in the FROM clause (which is to say, for each of the +** nested loops as implemented). The order of WhereLevel objects determines +** the loop nested order, with WhereInfo.a[0] being the outer loop and +** WhereInfo.a[WhereInfo.nLevel-1] being the inner loop. +*/ +struct WhereLevel { + int iLeftJoin; /* Memory cell used to implement LEFT OUTER JOIN */ + int iTabCur; /* The VDBE cursor used to access the table */ + int iIdxCur; /* The VDBE cursor used to access pIdx */ + int addrBrk; /* Jump here to break out of the loop */ + int addrNxt; /* Jump here to start the next IN combination */ + int addrSkip; /* Jump here for next iteration of skip-scan */ + int addrCont; /* Jump here to continue with the next loop cycle */ + int addrFirst; /* First instruction of interior of the loop */ + int addrBody; /* Beginning of the body of this loop */ + int regBignull; /* big-null flag reg. True if a NULL-scan is needed */ + int addrBignull; /* Jump here for next part of big-null scan */ +#ifndef SQLITE_LIKE_DOESNT_MATCH_BLOBS + u32 iLikeRepCntr; /* LIKE range processing counter register (times 2) */ + int addrLikeRep; /* LIKE range processing address */ +#endif + int regFilter; /* Bloom filter */ + WhereRightJoin *pRJ; /* Extra information for RIGHT JOIN */ + u8 iFrom; /* Which entry in the FROM clause */ + u8 op, p3, p5; /* Opcode, P3 & P5 of the opcode that ends the loop */ + int p1, p2; /* Operands of the opcode used to end the loop */ + union { /* Information that depends on pWLoop->wsFlags */ + struct { + int nIn; /* Number of entries in aInLoop[] */ + struct InLoop { + int iCur; /* The VDBE cursor used by this IN operator */ + int addrInTop; /* Top of the IN loop */ + int iBase; /* Base register of multi-key index record */ + int nPrefix; /* Number of prior entries in the key */ + u8 eEndLoopOp; /* IN Loop terminator. OP_Next or OP_Prev */ + } *aInLoop; /* Information about each nested IN operator */ + } in; /* Used when pWLoop->wsFlags&WHERE_IN_ABLE */ + Index *pCoveringIdx; /* Possible covering index for WHERE_MULTI_OR */ + } u; + struct WhereLoop *pWLoop; /* The selected WhereLoop object */ + Bitmask notReady; /* FROM entries not usable at this level */ +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + int addrVisit; /* Address at which row is visited */ +#endif +}; + +/* +** Each instance of this object represents an algorithm for evaluating one +** term of a join. Every term of the FROM clause will have at least +** one corresponding WhereLoop object (unless INDEXED BY constraints +** prevent a query solution - which is an error) and many terms of the +** FROM clause will have multiple WhereLoop objects, each describing a +** potential way of implementing that FROM-clause term, together with +** dependencies and cost estimates for using the chosen algorithm. +** +** Query planning consists of building up a collection of these WhereLoop +** objects, then computing a particular sequence of WhereLoop objects, with +** one WhereLoop object per FROM clause term, that satisfy all dependencies +** and that minimize the overall cost. +*/ +struct WhereLoop { + Bitmask prereq; /* Bitmask of other loops that must run first */ + Bitmask maskSelf; /* Bitmask identifying table iTab */ +#ifdef SQLITE_DEBUG + char cId; /* Symbolic ID of this loop for debugging use */ +#endif + u8 iTab; /* Position in FROM clause of table for this loop */ + u8 iSortIdx; /* Sorting index number. 0==None */ + LogEst rSetup; /* One-time setup cost (ex: create transient index) */ + LogEst rRun; /* Cost of running each loop */ + LogEst nOut; /* Estimated number of output rows */ + union { + struct { /* Information for internal btree tables */ + u16 nEq; /* Number of equality constraints */ + u16 nBtm; /* Size of BTM vector */ + u16 nTop; /* Size of TOP vector */ + u16 nDistinctCol; /* Index columns used to sort for DISTINCT */ + Index *pIndex; /* Index used, or NULL */ + } btree; + struct { /* Information for virtual tables */ + int idxNum; /* Index number */ + u32 needFree : 1; /* True if sqlite3_free(idxStr) is needed */ + u32 bOmitOffset : 1; /* True to let virtual table handle offset */ + i8 isOrdered; /* True if satisfies ORDER BY */ + u16 omitMask; /* Terms that may be omitted */ + char *idxStr; /* Index identifier string */ + u32 mHandleIn; /* Terms to handle as IN(...) instead of == */ + } vtab; + } u; + u32 wsFlags; /* WHERE_* flags describing the plan */ + u16 nLTerm; /* Number of entries in aLTerm[] */ + u16 nSkip; /* Number of NULL aLTerm[] entries */ + /**** whereLoopXfer() copies fields above ***********************/ +# define WHERE_LOOP_XFER_SZ offsetof(WhereLoop,nLSlot) + u16 nLSlot; /* Number of slots allocated for aLTerm[] */ + WhereTerm **aLTerm; /* WhereTerms used */ + WhereLoop *pNextLoop; /* Next WhereLoop object in the WhereClause */ + WhereTerm *aLTermSpace[3]; /* Initial aLTerm[] space */ +}; + +/* This object holds the prerequisites and the cost of running a +** subquery on one operand of an OR operator in the WHERE clause. +** See WhereOrSet for additional information +*/ +struct WhereOrCost { + Bitmask prereq; /* Prerequisites */ + LogEst rRun; /* Cost of running this subquery */ + LogEst nOut; /* Number of outputs for this subquery */ +}; + +/* The WhereOrSet object holds a set of possible WhereOrCosts that +** correspond to the subquery(s) of OR-clause processing. Only the +** best N_OR_COST elements are retained. +*/ +#define N_OR_COST 3 +struct WhereOrSet { + u16 n; /* Number of valid a[] entries */ + WhereOrCost a[N_OR_COST]; /* Set of best costs */ +}; + +/* +** Each instance of this object holds a sequence of WhereLoop objects +** that implement some or all of a query plan. +** +** Think of each WhereLoop object as a node in a graph with arcs +** showing dependencies and costs for travelling between nodes. (That is +** not a completely accurate description because WhereLoop costs are a +** vector, not a scalar, and because dependencies are many-to-one, not +** one-to-one as are graph nodes. But it is a useful visualization aid.) +** Then a WherePath object is a path through the graph that visits some +** or all of the WhereLoop objects once. +** +** The "solver" works by creating the N best WherePath objects of length +** 1. Then using those as a basis to compute the N best WherePath objects +** of length 2. And so forth until the length of WherePaths equals the +** number of nodes in the FROM clause. The best (lowest cost) WherePath +** at the end is the chosen query plan. +*/ +struct WherePath { + Bitmask maskLoop; /* Bitmask of all WhereLoop objects in this path */ + Bitmask revLoop; /* aLoop[]s that should be reversed for ORDER BY */ + LogEst nRow; /* Estimated number of rows generated by this path */ + LogEst rCost; /* Total cost of this path */ + LogEst rUnsorted; /* Total cost of this path ignoring sorting costs */ + i8 isOrdered; /* No. of ORDER BY terms satisfied. -1 for unknown */ + WhereLoop **aLoop; /* Array of WhereLoop objects implementing this path */ +}; + +/* +** The query generator uses an array of instances of this structure to +** help it analyze the subexpressions of the WHERE clause. Each WHERE +** clause subexpression is separated from the others by AND operators, +** usually, or sometimes subexpressions separated by OR. +** +** All WhereTerms are collected into a single WhereClause structure. +** The following identity holds: +** +** WhereTerm.pWC->a[WhereTerm.idx] == WhereTerm +** +** When a term is of the form: +** +** X <op> <expr> +** +** where X is a column name and <op> is one of certain operators, +** then WhereTerm.leftCursor and WhereTerm.u.leftColumn record the +** cursor number and column number for X. WhereTerm.eOperator records +** the <op> using a bitmask encoding defined by WO_xxx below. The +** use of a bitmask encoding for the operator allows us to search +** quickly for terms that match any of several different operators. +** +** A WhereTerm might also be two or more subterms connected by OR: +** +** (t1.X <op> <expr>) OR (t1.Y <op> <expr>) OR .... +** +** In this second case, wtFlag has the TERM_ORINFO bit set and eOperator==WO_OR +** and the WhereTerm.u.pOrInfo field points to auxiliary information that +** is collected about the OR clause. +** +** If a term in the WHERE clause does not match either of the two previous +** categories, then eOperator==0. The WhereTerm.pExpr field is still set +** to the original subexpression content and wtFlags is set up appropriately +** but no other fields in the WhereTerm object are meaningful. +** +** When eOperator!=0, prereqRight and prereqAll record sets of cursor numbers, +** but they do so indirectly. A single WhereMaskSet structure translates +** cursor number into bits and the translated bit is stored in the prereq +** fields. The translation is used in order to maximize the number of +** bits that will fit in a Bitmask. The VDBE cursor numbers might be +** spread out over the non-negative integers. For example, the cursor +** numbers might be 3, 8, 9, 10, 20, 23, 41, and 45. The WhereMaskSet +** translates these sparse cursor numbers into consecutive integers +** beginning with 0 in order to make the best possible use of the available +** bits in the Bitmask. So, in the example above, the cursor numbers +** would be mapped into integers 0 through 7. +** +** The number of terms in a join is limited by the number of bits +** in prereqRight and prereqAll. The default is 64 bits, hence SQLite +** is only able to process joins with 64 or fewer tables. +*/ +struct WhereTerm { + Expr *pExpr; /* Pointer to the subexpression that is this term */ + WhereClause *pWC; /* The clause this term is part of */ + LogEst truthProb; /* Probability of truth for this expression */ + u16 wtFlags; /* TERM_xxx bit flags. See below */ + u16 eOperator; /* A WO_xx value describing <op> */ + u8 nChild; /* Number of children that must disable us */ + u8 eMatchOp; /* Op for vtab MATCH/LIKE/GLOB/REGEXP terms */ + int iParent; /* Disable pWC->a[iParent] when this term disabled */ + int leftCursor; /* Cursor number of X in "X <op> <expr>" */ + union { + struct { + int leftColumn; /* Column number of X in "X <op> <expr>" */ + int iField; /* Field in (?,?,?) IN (SELECT...) vector */ + } x; /* Opcode other than OP_OR or OP_AND */ + WhereOrInfo *pOrInfo; /* Extra information if (eOperator & WO_OR)!=0 */ + WhereAndInfo *pAndInfo; /* Extra information if (eOperator& WO_AND)!=0 */ + } u; + Bitmask prereqRight; /* Bitmask of tables used by pExpr->pRight */ + Bitmask prereqAll; /* Bitmask of tables referenced by pExpr */ +}; + +/* +** Allowed values of WhereTerm.wtFlags +*/ +#define TERM_DYNAMIC 0x0001 /* Need to call sqlite3ExprDelete(db, pExpr) */ +#define TERM_VIRTUAL 0x0002 /* Added by the optimizer. Do not code */ +#define TERM_CODED 0x0004 /* This term is already coded */ +#define TERM_COPIED 0x0008 /* Has a child */ +#define TERM_ORINFO 0x0010 /* Need to free the WhereTerm.u.pOrInfo object */ +#define TERM_ANDINFO 0x0020 /* Need to free the WhereTerm.u.pAndInfo obj */ +#define TERM_OK 0x0040 /* Used during OR-clause processing */ +#define TERM_VNULL 0x0080 /* Manufactured x>NULL or x<=NULL term */ +#define TERM_LIKEOPT 0x0100 /* Virtual terms from the LIKE optimization */ +#define TERM_LIKECOND 0x0200 /* Conditionally this LIKE operator term */ +#define TERM_LIKE 0x0400 /* The original LIKE operator */ +#define TERM_IS 0x0800 /* Term.pExpr is an IS operator */ +#define TERM_VARSELECT 0x1000 /* Term.pExpr contains a correlated sub-query */ +#define TERM_HEURTRUTH 0x2000 /* Heuristic truthProb used */ +#ifdef SQLITE_ENABLE_STAT4 +# define TERM_HIGHTRUTH 0x4000 /* Term excludes few rows */ +#else +# define TERM_HIGHTRUTH 0 /* Only used with STAT4 */ +#endif +#define TERM_SLICE 0x8000 /* One slice of a row-value/vector comparison */ + +/* +** An instance of the WhereScan object is used as an iterator for locating +** terms in the WHERE clause that are useful to the query planner. +*/ +struct WhereScan { + WhereClause *pOrigWC; /* Original, innermost WhereClause */ + WhereClause *pWC; /* WhereClause currently being scanned */ + const char *zCollName; /* Required collating sequence, if not NULL */ + Expr *pIdxExpr; /* Search for this index expression */ + int k; /* Resume scanning at this->pWC->a[this->k] */ + u32 opMask; /* Acceptable operators */ + char idxaff; /* Must match this affinity, if zCollName!=NULL */ + unsigned char iEquiv; /* Current slot in aiCur[] and aiColumn[] */ + unsigned char nEquiv; /* Number of entries in aiCur[] and aiColumn[] */ + int aiCur[11]; /* Cursors in the equivalence class */ + i16 aiColumn[11]; /* Corresponding column number in the eq-class */ +}; + +/* +** An instance of the following structure holds all information about a +** WHERE clause. Mostly this is a container for one or more WhereTerms. +** +** Explanation of pOuter: For a WHERE clause of the form +** +** a AND ((b AND c) OR (d AND e)) AND f +** +** There are separate WhereClause objects for the whole clause and for +** the subclauses "(b AND c)" and "(d AND e)". The pOuter field of the +** subclauses points to the WhereClause object for the whole clause. +*/ +struct WhereClause { + WhereInfo *pWInfo; /* WHERE clause processing context */ + WhereClause *pOuter; /* Outer conjunction */ + u8 op; /* Split operator. TK_AND or TK_OR */ + u8 hasOr; /* True if any a[].eOperator is WO_OR */ + int nTerm; /* Number of terms */ + int nSlot; /* Number of entries in a[] */ + int nBase; /* Number of terms through the last non-Virtual */ + WhereTerm *a; /* Each a[] describes a term of the WHERE clause */ +#if defined(SQLITE_SMALL_STACK) + WhereTerm aStatic[1]; /* Initial static space for a[] */ +#else + WhereTerm aStatic[8]; /* Initial static space for a[] */ +#endif +}; + +/* +** A WhereTerm with eOperator==WO_OR has its u.pOrInfo pointer set to +** a dynamically allocated instance of the following structure. +*/ +struct WhereOrInfo { + WhereClause wc; /* Decomposition into subterms */ + Bitmask indexable; /* Bitmask of all indexable tables in the clause */ +}; + +/* +** A WhereTerm with eOperator==WO_AND has its u.pAndInfo pointer set to +** a dynamically allocated instance of the following structure. +*/ +struct WhereAndInfo { + WhereClause wc; /* The subexpression broken out */ +}; + +/* +** An instance of the following structure keeps track of a mapping +** between VDBE cursor numbers and bits of the bitmasks in WhereTerm. +** +** The VDBE cursor numbers are small integers contained in +** SrcItem.iCursor and Expr.iTable fields. For any given WHERE +** clause, the cursor numbers might not begin with 0 and they might +** contain gaps in the numbering sequence. But we want to make maximum +** use of the bits in our bitmasks. This structure provides a mapping +** from the sparse cursor numbers into consecutive integers beginning +** with 0. +** +** If WhereMaskSet.ix[A]==B it means that The A-th bit of a Bitmask +** corresponds VDBE cursor number B. The A-th bit of a bitmask is 1<<A. +** +** For example, if the WHERE clause expression used these VDBE +** cursors: 4, 5, 8, 29, 57, 73. Then the WhereMaskSet structure +** would map those cursor numbers into bits 0 through 5. +** +** Note that the mapping is not necessarily ordered. In the example +** above, the mapping might go like this: 4->3, 5->1, 8->2, 29->0, +** 57->5, 73->4. Or one of 719 other combinations might be used. It +** does not really matter. What is important is that sparse cursor +** numbers all get mapped into bit numbers that begin with 0 and contain +** no gaps. +*/ +struct WhereMaskSet { + int bVarSelect; /* Used by sqlite3WhereExprUsage() */ + int n; /* Number of assigned cursor values */ + int ix[BMS]; /* Cursor assigned to each bit */ +}; + +/* +** This object is a convenience wrapper holding all information needed +** to construct WhereLoop objects for a particular query. +*/ +struct WhereLoopBuilder { + WhereInfo *pWInfo; /* Information about this WHERE */ + WhereClause *pWC; /* WHERE clause terms */ + WhereLoop *pNew; /* Template WhereLoop */ + WhereOrSet *pOrSet; /* Record best loops here, if not NULL */ +#ifdef SQLITE_ENABLE_STAT4 + UnpackedRecord *pRec; /* Probe for stat4 (if required) */ + int nRecValid; /* Number of valid fields currently in pRec */ +#endif + unsigned char bldFlags1; /* First set of SQLITE_BLDF_* flags */ + unsigned char bldFlags2; /* Second set of SQLITE_BLDF_* flags */ + unsigned int iPlanLimit; /* Search limiter */ +}; + +/* Allowed values for WhereLoopBuider.bldFlags */ +#define SQLITE_BLDF1_INDEXED 0x0001 /* An index is used */ +#define SQLITE_BLDF1_UNIQUE 0x0002 /* All keys of a UNIQUE index used */ + +#define SQLITE_BLDF2_2NDPASS 0x0004 /* Second builder pass needed */ + +/* The WhereLoopBuilder.iPlanLimit is used to limit the number of +** index+constraint combinations the query planner will consider for a +** particular query. If this parameter is unlimited, then certain +** pathological queries can spend excess time in the sqlite3WhereBegin() +** routine. The limit is high enough that is should not impact real-world +** queries. +** +** SQLITE_QUERY_PLANNER_LIMIT is the baseline limit. The limit is +** increased by SQLITE_QUERY_PLANNER_LIMIT_INCR before each term of the FROM +** clause is processed, so that every table in a join is guaranteed to be +** able to propose a some index+constraint combinations even if the initial +** baseline limit was exhausted by prior tables of the join. +*/ +#ifndef SQLITE_QUERY_PLANNER_LIMIT +# define SQLITE_QUERY_PLANNER_LIMIT 20000 +#endif +#ifndef SQLITE_QUERY_PLANNER_LIMIT_INCR +# define SQLITE_QUERY_PLANNER_LIMIT_INCR 1000 +#endif + +/* +** The WHERE clause processing routine has two halves. The +** first part does the start of the WHERE loop and the second +** half does the tail of the WHERE loop. An instance of +** this structure is returned by the first half and passed +** into the second half to give some continuity. +** +** An instance of this object holds the complete state of the query +** planner. +*/ +struct WhereInfo { + Parse *pParse; /* Parsing and code generating context */ + SrcList *pTabList; /* List of tables in the join */ + ExprList *pOrderBy; /* The ORDER BY clause or NULL */ + ExprList *pResultSet; /* Result set of the query */ +#if WHERETRACE_ENABLED + Expr *pWhere; /* The complete WHERE clause */ +#endif + Select *pSelect; /* The entire SELECT statement containing WHERE */ + int aiCurOnePass[2]; /* OP_OpenWrite cursors for the ONEPASS opt */ + int iContinue; /* Jump here to continue with next record */ + int iBreak; /* Jump here to break out of the loop */ + int savedNQueryLoop; /* pParse->nQueryLoop outside the WHERE loop */ + u16 wctrlFlags; /* Flags originally passed to sqlite3WhereBegin() */ + LogEst iLimit; /* LIMIT if wctrlFlags has WHERE_USE_LIMIT */ + u8 nLevel; /* Number of nested loop */ + i8 nOBSat; /* Number of ORDER BY terms satisfied by indices */ + u8 eOnePass; /* ONEPASS_OFF, or _SINGLE, or _MULTI */ + u8 eDistinct; /* One of the WHERE_DISTINCT_* values */ + unsigned bDeferredSeek :1; /* Uses OP_DeferredSeek */ + unsigned untestedTerms :1; /* Not all WHERE terms resolved by outer loop */ + unsigned bOrderedInnerLoop:1;/* True if only the inner-most loop is ordered */ + unsigned sorted :1; /* True if really sorted (not just grouped) */ + LogEst nRowOut; /* Estimated number of output rows */ + int iTop; /* The very beginning of the WHERE loop */ + int iEndWhere; /* End of the WHERE clause itself */ + WhereLoop *pLoops; /* List of all WhereLoop objects */ + WhereMemBlock *pMemToFree;/* Memory to free when this object destroyed */ + Bitmask revMask; /* Mask of ORDER BY terms that need reversing */ + WhereClause sWC; /* Decomposition of the WHERE clause */ + WhereMaskSet sMaskSet; /* Map cursor numbers to bitmasks */ + WhereLevel a[1]; /* Information about each nest loop in WHERE */ +}; + +/* +** Private interfaces - callable only by other where.c routines. +** +** where.c: +*/ +Bitmask sqlite3WhereGetMask(WhereMaskSet*,int); +#ifdef WHERETRACE_ENABLED +void sqlite3WhereClausePrint(WhereClause *pWC); +void sqlite3WhereTermPrint(WhereTerm *pTerm, int iTerm); +void sqlite3WhereLoopPrint(const WhereLoop *p, const WhereClause *pWC); +#endif +WhereTerm *sqlite3WhereFindTerm( + WhereClause *pWC, /* The WHERE clause to be searched */ + int iCur, /* Cursor number of LHS */ + int iColumn, /* Column number of LHS */ + Bitmask notReady, /* RHS must not overlap with this mask */ + u32 op, /* Mask of WO_xx values describing operator */ + Index *pIdx /* Must be compatible with this index, if not NULL */ +); +void *sqlite3WhereMalloc(WhereInfo *pWInfo, u64 nByte); +void *sqlite3WhereRealloc(WhereInfo *pWInfo, void *pOld, u64 nByte); + +/* wherecode.c: */ +#ifndef SQLITE_OMIT_EXPLAIN +int sqlite3WhereExplainOneScan( + Parse *pParse, /* Parse context */ + SrcList *pTabList, /* Table list this loop refers to */ + WhereLevel *pLevel, /* Scan to write OP_Explain opcode for */ + u16 wctrlFlags /* Flags passed to sqlite3WhereBegin() */ +); +int sqlite3WhereExplainBloomFilter( + const Parse *pParse, /* Parse context */ + const WhereInfo *pWInfo, /* WHERE clause */ + const WhereLevel *pLevel /* Bloom filter on this level */ +); +#else +# define sqlite3WhereExplainOneScan(u,v,w,x) 0 +# define sqlite3WhereExplainBloomFilter(u,v,w) 0 +#endif /* SQLITE_OMIT_EXPLAIN */ +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS +void sqlite3WhereAddScanStatus( + Vdbe *v, /* Vdbe to add scanstatus entry to */ + SrcList *pSrclist, /* FROM clause pLvl reads data from */ + WhereLevel *pLvl, /* Level to add scanstatus() entry for */ + int addrExplain /* Address of OP_Explain (or 0) */ +); +#else +# define sqlite3WhereAddScanStatus(a, b, c, d) ((void)d) +#endif +Bitmask sqlite3WhereCodeOneLoopStart( + Parse *pParse, /* Parsing context */ + Vdbe *v, /* Prepared statement under construction */ + WhereInfo *pWInfo, /* Complete information about the WHERE clause */ + int iLevel, /* Which level of pWInfo->a[] should be coded */ + WhereLevel *pLevel, /* The current level pointer */ + Bitmask notReady /* Which tables are currently available */ +); +SQLITE_NOINLINE void sqlite3WhereRightJoinLoop( + WhereInfo *pWInfo, + int iLevel, + WhereLevel *pLevel +); + +/* whereexpr.c: */ +void sqlite3WhereClauseInit(WhereClause*,WhereInfo*); +void sqlite3WhereClauseClear(WhereClause*); +void sqlite3WhereSplit(WhereClause*,Expr*,u8); +void sqlite3WhereAddLimit(WhereClause*, Select*); +Bitmask sqlite3WhereExprUsage(WhereMaskSet*, Expr*); +Bitmask sqlite3WhereExprUsageNN(WhereMaskSet*, Expr*); +Bitmask sqlite3WhereExprListUsage(WhereMaskSet*, ExprList*); +void sqlite3WhereExprAnalyze(SrcList*, WhereClause*); +void sqlite3WhereTabFuncArgs(Parse*, SrcItem*, WhereClause*); + + + + + +/* +** Bitmasks for the operators on WhereTerm objects. These are all +** operators that are of interest to the query planner. An +** OR-ed combination of these values can be used when searching for +** particular WhereTerms within a WhereClause. +** +** Value constraints: +** WO_EQ == SQLITE_INDEX_CONSTRAINT_EQ +** WO_LT == SQLITE_INDEX_CONSTRAINT_LT +** WO_LE == SQLITE_INDEX_CONSTRAINT_LE +** WO_GT == SQLITE_INDEX_CONSTRAINT_GT +** WO_GE == SQLITE_INDEX_CONSTRAINT_GE +*/ +#define WO_IN 0x0001 +#define WO_EQ 0x0002 +#define WO_LT (WO_EQ<<(TK_LT-TK_EQ)) +#define WO_LE (WO_EQ<<(TK_LE-TK_EQ)) +#define WO_GT (WO_EQ<<(TK_GT-TK_EQ)) +#define WO_GE (WO_EQ<<(TK_GE-TK_EQ)) +#define WO_AUX 0x0040 /* Op useful to virtual tables only */ +#define WO_IS 0x0080 +#define WO_ISNULL 0x0100 +#define WO_OR 0x0200 /* Two or more OR-connected terms */ +#define WO_AND 0x0400 /* Two or more AND-connected terms */ +#define WO_EQUIV 0x0800 /* Of the form A==B, both columns */ +#define WO_NOOP 0x1000 /* This term does not restrict search space */ +#define WO_ROWVAL 0x2000 /* A row-value term */ + +#define WO_ALL 0x3fff /* Mask of all possible WO_* values */ +#define WO_SINGLE 0x01ff /* Mask of all non-compound WO_* values */ + +/* +** These are definitions of bits in the WhereLoop.wsFlags field. +** The particular combination of bits in each WhereLoop help to +** determine the algorithm that WhereLoop represents. +*/ +#define WHERE_COLUMN_EQ 0x00000001 /* x=EXPR */ +#define WHERE_COLUMN_RANGE 0x00000002 /* x<EXPR and/or x>EXPR */ +#define WHERE_COLUMN_IN 0x00000004 /* x IN (...) */ +#define WHERE_COLUMN_NULL 0x00000008 /* x IS NULL */ +#define WHERE_CONSTRAINT 0x0000000f /* Any of the WHERE_COLUMN_xxx values */ +#define WHERE_TOP_LIMIT 0x00000010 /* x<EXPR or x<=EXPR constraint */ +#define WHERE_BTM_LIMIT 0x00000020 /* x>EXPR or x>=EXPR constraint */ +#define WHERE_BOTH_LIMIT 0x00000030 /* Both x>EXPR and x<EXPR */ +#define WHERE_IDX_ONLY 0x00000040 /* Use index only - omit table */ +#define WHERE_IPK 0x00000100 /* x is the INTEGER PRIMARY KEY */ +#define WHERE_INDEXED 0x00000200 /* WhereLoop.u.btree.pIndex is valid */ +#define WHERE_VIRTUALTABLE 0x00000400 /* WhereLoop.u.vtab is valid */ +#define WHERE_IN_ABLE 0x00000800 /* Able to support an IN operator */ +#define WHERE_ONEROW 0x00001000 /* Selects no more than one row */ +#define WHERE_MULTI_OR 0x00002000 /* OR using multiple indices */ +#define WHERE_AUTO_INDEX 0x00004000 /* Uses an ephemeral index */ +#define WHERE_SKIPSCAN 0x00008000 /* Uses the skip-scan algorithm */ +#define WHERE_UNQ_WANTED 0x00010000 /* WHERE_ONEROW would have been helpful*/ +#define WHERE_PARTIALIDX 0x00020000 /* The automatic index is partial */ +#define WHERE_IN_EARLYOUT 0x00040000 /* Perhaps quit IN loops early */ +#define WHERE_BIGNULL_SORT 0x00080000 /* Column nEq of index is BIGNULL */ +#define WHERE_IN_SEEKSCAN 0x00100000 /* Seek-scan optimization for IN */ +#define WHERE_TRANSCONS 0x00200000 /* Uses a transitive constraint */ +#define WHERE_BLOOMFILTER 0x00400000 /* Consider using a Bloom-filter */ +#define WHERE_SELFCULL 0x00800000 /* nOut reduced by extra WHERE terms */ +#define WHERE_OMIT_OFFSET 0x01000000 /* Set offset counter to zero */ + /* 0x02000000 -- available for reuse */ +#define WHERE_EXPRIDX 0x04000000 /* Uses an index-on-expressions */ + +#endif /* !defined(SQLITE_WHEREINT_H) */ |