drh
0bd1f4ea5a
in the parser to make the parse tables much smaller. This reduced the size of the library by 15K. (CVS 605) FossilOrigin-Name: 7ac5bd293cbb2bf252f31f1571f7efac7e77280a
903 lines
40 KiB
C
903 lines
40 KiB
C
/*
|
|
** 2001 September 15
|
|
**
|
|
** 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.
|
|
**
|
|
*************************************************************************
|
|
** Internal interface definitions for SQLite.
|
|
**
|
|
** @(#) $Id: sqliteInt.h,v 1.120 2002/06/06 18:54:41 drh Exp $
|
|
*/
|
|
#include "sqlite.h"
|
|
#include "hash.h"
|
|
#include "vdbe.h"
|
|
#include "parse.h"
|
|
#include "btree.h"
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <assert.h>
|
|
|
|
/*
|
|
** The maximum number of in-memory pages to use for the main database
|
|
** table and for temporary tables.
|
|
*/
|
|
#define MAX_PAGES 2000
|
|
#define TEMP_PAGES 500
|
|
|
|
/*
|
|
** If the following macro is set to 1, then NULL values are considered
|
|
** distinct for the SELECT DISTINCT statement and for UNION or EXCEPT
|
|
** compound queries. No other SQL database engine (among those tested)
|
|
** works this way except for OCELOT. But the SQL92 spec implies that
|
|
** this is how things should work.
|
|
**
|
|
** If the following macro is set to 0, then NULLs are indistinct for
|
|
** SELECT DISTINCT and for UNION.
|
|
*/
|
|
#define NULL_ALWAYS_DISTINCT 0
|
|
|
|
/*
|
|
** If the following macro is set to 1, then NULL values are considered
|
|
** distinct when determining whether or not two entries are the same
|
|
** in a UNIQUE index. This is the way PostgreSQL, Oracle, DB2, MySQL,
|
|
** OCELOT, and Firebird all work. The SQL92 spec explicitly says this
|
|
** is the way things are suppose to work.
|
|
**
|
|
** If the following macro is set to 0, the NULLs are indistinct for
|
|
** a UNIQUE index. In this mode, you can only have a single NULL entry
|
|
** for a column declared UNIQUE. This is the way Informix and SQL Server
|
|
** work.
|
|
*/
|
|
#define NULL_DISTINCT_FOR_UNIQUE 1
|
|
|
|
/*
|
|
** Integers of known sizes. These typedefs might change for architectures
|
|
** where the sizes very. Preprocessor macros are available so that the
|
|
** types can be conveniently redefined at compile-type. Like this:
|
|
**
|
|
** cc '-DUINTPTR_TYPE=long long int' ...
|
|
*/
|
|
#ifndef UINT32_TYPE
|
|
# define UINT32_TYPE unsigned int
|
|
#endif
|
|
#ifndef UINT16_TYPE
|
|
# define UINT16_TYPE unsigned short int
|
|
#endif
|
|
#ifndef UINT8_TYPE
|
|
# define UINT8_TYPE unsigned char
|
|
#endif
|
|
#ifndef INTPTR_TYPE
|
|
# define INTPTR_TYPE int
|
|
#endif
|
|
typedef UINT32_TYPE u32; /* 4-byte unsigned integer */
|
|
typedef UINT16_TYPE u16; /* 2-byte unsigned integer */
|
|
typedef UINT8_TYPE u8; /* 1-byte unsigned integer */
|
|
typedef INTPTR_TYPE ptr; /* Big enough to hold a pointer */
|
|
typedef unsigned INTPTR_TYPE uptr; /* Big enough to hold a pointer */
|
|
|
|
/*
|
|
** This macro casts a pointer to an integer. Useful for doing
|
|
** pointer arithmetic.
|
|
*/
|
|
#define Addr(X) ((uptr)X)
|
|
|
|
/*
|
|
** The maximum number of bytes of data that can be put into a single
|
|
** row of a single table. The upper bound on this limit is 16777215
|
|
** bytes (or 16MB-1). We have arbitrarily set the limit to just 1MB
|
|
** here because the overflow page chain is inefficient for really big
|
|
** records and we want to discourage people from thinking that
|
|
** multi-megabyte records are OK. If your needs are different, you can
|
|
** change this define and recompile to increase or decrease the record
|
|
** size.
|
|
*/
|
|
#define MAX_BYTES_PER_ROW 1048576
|
|
|
|
/*
|
|
** If memory allocation problems are found, recompile with
|
|
**
|
|
** -DMEMORY_DEBUG=1
|
|
**
|
|
** to enable some sanity checking on malloc() and free(). To
|
|
** check for memory leaks, recompile with
|
|
**
|
|
** -DMEMORY_DEBUG=2
|
|
**
|
|
** and a line of text will be written to standard error for
|
|
** each malloc() and free(). This output can be analyzed
|
|
** by an AWK script to determine if there are any leaks.
|
|
*/
|
|
#ifdef MEMORY_DEBUG
|
|
# define sqliteMalloc(X) sqliteMalloc_(X,__FILE__,__LINE__)
|
|
# define sqliteFree(X) sqliteFree_(X,__FILE__,__LINE__)
|
|
# define sqliteRealloc(X,Y) sqliteRealloc_(X,Y,__FILE__,__LINE__)
|
|
# define sqliteStrDup(X) sqliteStrDup_(X,__FILE__,__LINE__)
|
|
# define sqliteStrNDup(X,Y) sqliteStrNDup_(X,Y,__FILE__,__LINE__)
|
|
void sqliteStrRealloc(char**);
|
|
#else
|
|
# define sqliteStrRealloc(X)
|
|
#endif
|
|
|
|
/*
|
|
** This variable gets set if malloc() ever fails. After it gets set,
|
|
** the SQLite library shuts down permanently.
|
|
*/
|
|
extern int sqlite_malloc_failed;
|
|
|
|
/*
|
|
** The following global variables are used for testing and debugging
|
|
** only. They only work if MEMORY_DEBUG is defined.
|
|
*/
|
|
#ifdef MEMORY_DEBUG
|
|
extern int sqlite_nMalloc; /* Number of sqliteMalloc() calls */
|
|
extern int sqlite_nFree; /* Number of sqliteFree() calls */
|
|
extern int sqlite_iMallocFail; /* Fail sqliteMalloc() after this many calls */
|
|
#endif
|
|
|
|
/*
|
|
** Name of the master database table. The master database table
|
|
** is a special table that holds the names and attributes of all
|
|
** user tables and indices.
|
|
*/
|
|
#define MASTER_NAME "sqlite_master"
|
|
|
|
/*
|
|
** A convenience macro that returns the number of elements in
|
|
** an array.
|
|
*/
|
|
#define ArraySize(X) (sizeof(X)/sizeof(X[0]))
|
|
|
|
/*
|
|
** Forward references to structures
|
|
*/
|
|
typedef struct Column Column;
|
|
typedef struct Table Table;
|
|
typedef struct Index Index;
|
|
typedef struct Instruction Instruction;
|
|
typedef struct Expr Expr;
|
|
typedef struct ExprList ExprList;
|
|
typedef struct Parse Parse;
|
|
typedef struct Token Token;
|
|
typedef struct IdList IdList;
|
|
typedef struct SrcList SrcList;
|
|
typedef struct WhereInfo WhereInfo;
|
|
typedef struct WhereLevel WhereLevel;
|
|
typedef struct Select Select;
|
|
typedef struct AggExpr AggExpr;
|
|
typedef struct FuncDef FuncDef;
|
|
typedef struct Trigger Trigger;
|
|
typedef struct TriggerStep TriggerStep;
|
|
typedef struct TriggerStack TriggerStack;
|
|
|
|
/*
|
|
** Each database is an instance of the following structure
|
|
*/
|
|
struct sqlite {
|
|
Btree *pBe; /* The B*Tree backend */
|
|
Btree *pBeTemp; /* Backend for session temporary tables */
|
|
int flags; /* Miscellanous flags. See below */
|
|
int file_format; /* What file format version is this database? */
|
|
int schema_cookie; /* Magic number that changes with the schema */
|
|
int next_cookie; /* Value of schema_cookie after commit */
|
|
int cache_size; /* Number of pages to use in the cache */
|
|
int nTable; /* Number of tables in the database */
|
|
void *pBusyArg; /* 1st Argument to the busy callback */
|
|
int (*xBusyCallback)(void *,const char*,int); /* The busy callback */
|
|
Hash tblHash; /* All tables indexed by name */
|
|
Hash idxHash; /* All (named) indices indexed by name */
|
|
Hash tblDrop; /* Uncommitted DROP TABLEs */
|
|
Hash idxDrop; /* Uncommitted DROP INDEXs */
|
|
Hash aFunc; /* All functions that can be in SQL exprs */
|
|
int lastRowid; /* ROWID of most recent insert */
|
|
int priorNewRowid; /* Last randomly generated ROWID */
|
|
int onError; /* Default conflict algorithm */
|
|
int magic; /* Magic number for detect library misuse */
|
|
int nChange; /* Number of rows changed */
|
|
int recursionDepth; /* Number of nested calls to sqlite_exec() */
|
|
|
|
Hash trigHash; /* All triggers indexed by name */
|
|
Hash trigDrop; /* Uncommited dropped triggers */
|
|
};
|
|
|
|
/*
|
|
** Possible values for the sqlite.flags.
|
|
*/
|
|
#define SQLITE_VdbeTrace 0x00000001 /* True to trace VDBE execution */
|
|
#define SQLITE_Initialized 0x00000002 /* True after initialization */
|
|
#define SQLITE_Interrupt 0x00000004 /* Cancel current operation */
|
|
#define SQLITE_InTrans 0x00000008 /* True if in a transaction */
|
|
#define SQLITE_InternChanges 0x00000010 /* Uncommitted Hash table changes */
|
|
#define SQLITE_FullColNames 0x00000020 /* Show full column names on SELECT */
|
|
#define SQLITE_CountRows 0x00000040 /* Count rows changed by INSERT, */
|
|
/* DELETE, or UPDATE and return */
|
|
/* the count using a callback. */
|
|
#define SQLITE_NullCallback 0x00000080 /* Invoke the callback once if the */
|
|
/* result set is empty */
|
|
#define SQLITE_ResultDetails 0x00000100 /* Details added to result set */
|
|
#define SQLITE_UnresetViews 0x00000200 /* True if one or more views have */
|
|
/* defined column names */
|
|
|
|
/*
|
|
** Possible values for the sqlite.magic field.
|
|
** The numbers are obtained at random and have no special meaning, other
|
|
** than being distinct from one another.
|
|
*/
|
|
#define SQLITE_MAGIC_OPEN 0xa029a697 /* Database is open */
|
|
#define SQLITE_MAGIC_CLOSED 0x9f3c2d33 /* Database is closed */
|
|
#define SQLITE_MAGIC_BUSY 0xf03b7906 /* Database currently in use */
|
|
#define SQLITE_MAGIC_ERROR 0xb5357930 /* An SQLITE_MISUSE error occurred */
|
|
|
|
/*
|
|
** Each SQL function is defined by an instance of the following
|
|
** structure. A pointer to this structure is stored in the sqlite.aFunc
|
|
** hash table. When multiple functions have the same name, the hash table
|
|
** points to a linked list of these structures.
|
|
*/
|
|
struct FuncDef {
|
|
void (*xFunc)(sqlite_func*,int,const char**); /* Regular function */
|
|
void (*xStep)(sqlite_func*,int,const char**); /* Aggregate function step */
|
|
void (*xFinalize)(sqlite_func*); /* Aggregate function finializer */
|
|
int nArg; /* Number of arguments */
|
|
void *pUserData; /* User data parameter */
|
|
FuncDef *pNext; /* Next function with same name */
|
|
};
|
|
|
|
/*
|
|
** information about each column of an SQL table is held in an instance
|
|
** of this structure.
|
|
*/
|
|
struct Column {
|
|
char *zName; /* Name of this column */
|
|
char *zDflt; /* Default value of this column */
|
|
char *zType; /* Data type for this column */
|
|
u8 notNull; /* True if there is a NOT NULL constraint */
|
|
u8 isPrimKey; /* True if this column is an INTEGER PRIMARY KEY */
|
|
};
|
|
|
|
/*
|
|
** Each SQL table is represented in memory by an instance of the
|
|
** following structure.
|
|
**
|
|
** Expr.zName is the name of the table. The case of the original
|
|
** CREATE TABLE statement is stored, but case is not significant for
|
|
** comparisons.
|
|
**
|
|
** Expr.nCol is the number of columns in this table. Expr.aCol is a
|
|
** pointer to an array of Column structures, one for each column.
|
|
**
|
|
** If the table has an INTEGER PRIMARY KEY, then Expr.iPKey is the index of
|
|
** the column that is that key. Otherwise Expr.iPKey is negative. Note
|
|
** that the datatype of the PRIMARY KEY must be INTEGER for this field to
|
|
** be set. An INTEGER PRIMARY KEY is used as the rowid for each row of
|
|
** the table. If a table has no INTEGER PRIMARY KEY, then a random rowid
|
|
** is generated for each row of the table. Expr.hasPrimKey is true if
|
|
** the table has any PRIMARY KEY, INTEGER or otherwise.
|
|
**
|
|
** Expr.tnum is the page number for the root BTree page of the table in the
|
|
** database file. If Expr.isTemp is true, then this page occurs in the
|
|
** auxiliary database file, not the main database file. If Expr.isTransient
|
|
** is true, then the table is stored in a file that is automatically deleted
|
|
** when the VDBE cursor to the table is closed. In this case Expr.tnum
|
|
** refers VDBE cursor number that holds the table open, not to the root
|
|
** page number. Transient tables are used to hold the results of a
|
|
** sub-query that appears instead of a real table name in the FROM clause
|
|
** of a SELECT statement.
|
|
*/
|
|
struct Table {
|
|
char *zName; /* Name of the table */
|
|
int nCol; /* Number of columns in this table */
|
|
Column *aCol; /* Information about each column */
|
|
int iPKey; /* If not less then 0, use aCol[iPKey] as the primary key */
|
|
Index *pIndex; /* List of SQL indexes on this table. */
|
|
int tnum; /* Root BTree node for this table (see note above) */
|
|
Select *pSelect; /* NULL for tables. Points to definition if a view. */
|
|
u8 readOnly; /* True if this table should not be written by the user */
|
|
u8 isCommit; /* True if creation of this table has been committed */
|
|
u8 isTemp; /* True if stored in db->pBeTemp instead of db->pBe */
|
|
u8 isTransient; /* True if automatically deleted when VDBE finishes */
|
|
u8 hasPrimKey; /* True if there exists a primary key */
|
|
u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */
|
|
|
|
Trigger *pTrigger; /* List of SQL triggers on this table */
|
|
};
|
|
|
|
/*
|
|
** SQLite supports 5 different ways to resolve a contraint
|
|
** error. ROLLBACK processing means that a constraint violation
|
|
** causes the operation in process to fail and for the current transaction
|
|
** to be rolled back. ABORT processing means the operation in process
|
|
** fails and any prior changes from that one operation are backed out,
|
|
** but the transaction is not rolled back. FAIL processing means that
|
|
** the operation in progress stops and returns an error code. But prior
|
|
** changes due to the same operation are not backed out and no rollback
|
|
** occurs. IGNORE means that the particular row that caused the constraint
|
|
** error is not inserted or updated. Processing continues and no error
|
|
** is returned. REPLACE means that preexisting database rows that caused
|
|
** a UNIQUE constraint violation are removed so that the new insert or
|
|
** update can proceed. Processing continues and no error is reported.
|
|
**
|
|
** The following there symbolic values are used to record which type
|
|
** of action to take.
|
|
*/
|
|
#define OE_None 0 /* There is no constraint to check */
|
|
#define OE_Rollback 1 /* Fail the operation and rollback the transaction */
|
|
#define OE_Abort 2 /* Back out changes but do no rollback transaction */
|
|
#define OE_Fail 3 /* Stop the operation but leave all prior changes */
|
|
#define OE_Ignore 4 /* Ignore the error. Do not do the INSERT or UPDATE */
|
|
#define OE_Replace 5 /* Delete existing record, then do INSERT or UPDATE */
|
|
#define OE_Default 9 /* Do whatever the default action is */
|
|
|
|
/*
|
|
** Each SQL index is represented in memory by an
|
|
** instance of the following structure.
|
|
**
|
|
** The columns of the table that are to be indexed are described
|
|
** by the aiColumn[] field of this structure. For example, suppose
|
|
** we have the following table and index:
|
|
**
|
|
** CREATE TABLE Ex1(c1 int, c2 int, c3 text);
|
|
** CREATE INDEX Ex2 ON Ex1(c3,c1);
|
|
**
|
|
** In the Table structure describing Ex1, nCol==3 because there are
|
|
** three columns in the table. In the Index structure describing
|
|
** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
|
|
** The value of aiColumn is {2, 0}. aiColumn[0]==2 because the
|
|
** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
|
|
** The second column to be indexed (c1) has an index of 0 in
|
|
** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
|
|
*/
|
|
struct Index {
|
|
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 */
|
|
Table *pTable; /* The SQL table being indexed */
|
|
int tnum; /* Page containing root of this index in database file */
|
|
u8 isUnique; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
|
|
u8 isCommit; /* True if creation of this index has been committed */
|
|
u8 isDropped; /* True if a DROP INDEX has executed on this index */
|
|
u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
|
|
Index *pNext; /* The next index associated with the same table */
|
|
};
|
|
|
|
/*
|
|
** Each token coming out of the lexer is an instance of
|
|
** this structure.
|
|
*/
|
|
struct Token {
|
|
const char *z; /* Text of the token. Not NULL-terminated! */
|
|
int n; /* Number of characters in this token */
|
|
};
|
|
|
|
/*
|
|
** Each node of an expression in the parse tree is an instance
|
|
** of this structure.
|
|
**
|
|
** Expr.op is the opcode. The integer parser token codes are reused
|
|
** as opcodes here. For example, the parser defines TK_GE to be an integer
|
|
** code representing the ">=" operator. This same integer code is reused
|
|
** to represent the greater-than-or-equal-to operator in the expression
|
|
** tree.
|
|
**
|
|
** Expr.pRight and Expr.pLeft are subexpressions. Expr.pList is a list
|
|
** of argument if the expression is a function.
|
|
**
|
|
** Expr.token is the operator token for this node. Expr.span is the complete
|
|
** subexpression represented by this node and all its decendents. These
|
|
** fields are used for error reporting and for reconstructing the text of
|
|
** an expression to use as the column name in a SELECT statement.
|
|
**
|
|
** An expression of the form ID or ID.ID refers to a column in a table.
|
|
** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
|
|
** the integer cursor number of a VDBE cursor pointing to that table and
|
|
** Expr.iColumn is the column number for the specific column. If the
|
|
** expression is used as a result in an aggregate SELECT, then the
|
|
** value is also stored in the Expr.iAgg column in the aggregate so that
|
|
** it can be accessed after all aggregates are computed.
|
|
**
|
|
** If the expression is a function, the Expr.iTable is an integer code
|
|
** representing which function.
|
|
**
|
|
** The Expr.pSelect field points to a SELECT statement. The SELECT might
|
|
** be the right operand of an IN operator. Or, if a scalar SELECT appears
|
|
** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
|
|
** operand.
|
|
*/
|
|
struct Expr {
|
|
int op; /* Operation performed by this node */
|
|
Expr *pLeft, *pRight; /* Left and right subnodes */
|
|
ExprList *pList; /* A list of expressions used as a function argument */
|
|
Token token; /* An operand token */
|
|
Token span; /* Complete text of the expression */
|
|
int iTable, iColumn; /* When op==TK_COLUMN, then this expr node means the
|
|
** iColumn-th field of the iTable-th table. When
|
|
** op==TK_FUNCTION, iColumn holds the function id */
|
|
int iAgg; /* When op==TK_COLUMN and pParse->useAgg==TRUE, pull
|
|
** result from the iAgg-th element of the aggregator */
|
|
Select *pSelect; /* When the expression is a sub-select */
|
|
};
|
|
|
|
/*
|
|
** A list of expressions. Each expression may optionally have a
|
|
** name. An expr/name combination can be used in several ways, such
|
|
** as the list of "expr AS ID" fields following a "SELECT" or in the
|
|
** list of "ID = expr" items in an UPDATE. A list of expressions can
|
|
** also be used as the argument to a function, in which case the a.zName
|
|
** field is not used.
|
|
*/
|
|
struct ExprList {
|
|
int nExpr; /* Number of expressions on the list */
|
|
struct ExprList_item {
|
|
Expr *pExpr; /* The list of expressions */
|
|
char *zName; /* Token associated with this expression */
|
|
char sortOrder; /* 1 for DESC or 0 for ASC */
|
|
char isAgg; /* True if this is an aggregate like count(*) */
|
|
char done; /* A flag to indicate when processing is finished */
|
|
} *a; /* One entry for each expression */
|
|
};
|
|
|
|
/*
|
|
** An instance of this structure can hold a simple list of identifiers,
|
|
** such as the list "a,b,c" in the following statements:
|
|
**
|
|
** INSERT INTO t(a,b,c) VALUES ...;
|
|
** CREATE INDEX idx ON t(a,b,c);
|
|
** CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
|
|
**
|
|
** The IdList.a.idx field is used when the IdList represents the list of
|
|
** column names after a table name in an INSERT statement. In the statement
|
|
**
|
|
** INSERT INTO t(a,b,c) ...
|
|
**
|
|
** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
|
|
*/
|
|
struct IdList {
|
|
int nId; /* Number of identifiers on the list */
|
|
struct IdList_item {
|
|
char *zName; /* Name of the identifier */
|
|
int idx; /* Index in some Table.aCol[] of a column named zName */
|
|
} *a;
|
|
};
|
|
|
|
/*
|
|
** The following structure describes the FROM clause of a SELECT statement.
|
|
** Each table or subquery in the FROM clause is a separate element of
|
|
** the SrcList.a[] array.
|
|
*/
|
|
struct SrcList {
|
|
int nSrc; /* Number of tables or subqueries in the FROM clause */
|
|
struct SrcList_item {
|
|
char *zName; /* Name of the table */
|
|
char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */
|
|
Table *pTab; /* An SQL table corresponding to zName */
|
|
Select *pSelect; /* A SELECT statement used in place of a table name */
|
|
int jointype; /* Type of join between this table and the next */
|
|
Expr *pOn; /* The ON clause of a join */
|
|
IdList *pUsing; /* The USING clause of a join */
|
|
} *a; /* One entry for each identifier on the list */
|
|
};
|
|
|
|
/*
|
|
** Permitted values of the SrcList.a.jointype field
|
|
*/
|
|
#define JT_INNER 0x0001 /* Any kind of inner or cross join */
|
|
#define JT_NATURAL 0x0002 /* True for a "natural" join */
|
|
#define JT_LEFT 0x0004 /* Left outer join */
|
|
#define JT_RIGHT 0x0008 /* Right outer join */
|
|
#define JT_OUTER 0x0010 /* The "OUTER" keyword is present */
|
|
#define JT_ERROR 0x0020 /* unknown or unsupported join type */
|
|
|
|
/*
|
|
** For each nested loop in a WHERE clause implementation, the WhereInfo
|
|
** structure contains a single instance of this structure. This structure
|
|
** is intended to be private the the where.c module and should not be
|
|
** access or modified by other modules.
|
|
*/
|
|
struct WhereLevel {
|
|
int iMem; /* Memory cell used by this level */
|
|
Index *pIdx; /* Index used */
|
|
int iCur; /* Cursor number used for this index */
|
|
int score; /* How well this indexed scored */
|
|
int brk; /* Jump here to break out of the loop */
|
|
int cont; /* Jump here to continue with the next loop cycle */
|
|
int op, p1, p2; /* Opcode used to terminate the loop */
|
|
int iLeftJoin; /* Memory cell used to implement LEFT OUTER JOIN */
|
|
int top; /* First instruction of interior of the loop */
|
|
};
|
|
|
|
/*
|
|
** 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.
|
|
*/
|
|
struct WhereInfo {
|
|
Parse *pParse;
|
|
SrcList *pTabList; /* List of tables in the join */
|
|
int iContinue; /* Jump here to continue with next record */
|
|
int iBreak; /* Jump here to break out of the loop */
|
|
int base; /* Index of first Open opcode */
|
|
int nLevel; /* Number of nested loop */
|
|
int savedNTab; /* Value of pParse->nTab before WhereBegin() */
|
|
int peakNTab; /* Value of pParse->nTab after WhereBegin() */
|
|
WhereLevel a[1]; /* Information about each nest loop in the WHERE */
|
|
};
|
|
|
|
/*
|
|
** An instance of the following structure contains all information
|
|
** needed to generate code for a single SELECT statement.
|
|
**
|
|
** The zSelect field is used when the Select structure must be persistent.
|
|
** Normally, the expression tree points to tokens in the original input
|
|
** string that encodes the select. But if the Select structure must live
|
|
** longer than its input string (for example when it is used to describe
|
|
** a VIEW) we have to make a copy of the input string so that the nodes
|
|
** of the expression tree will have something to point to. zSelect is used
|
|
** to hold that copy.
|
|
*/
|
|
struct Select {
|
|
int isDistinct; /* True if the DISTINCT keyword is present */
|
|
ExprList *pEList; /* The fields of the result */
|
|
SrcList *pSrc; /* The FROM clause */
|
|
Expr *pWhere; /* The WHERE clause */
|
|
ExprList *pGroupBy; /* The GROUP BY clause */
|
|
Expr *pHaving; /* The HAVING clause */
|
|
ExprList *pOrderBy; /* The ORDER BY clause */
|
|
int op; /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
|
|
Select *pPrior; /* Prior select in a compound select statement */
|
|
int nLimit, nOffset; /* LIMIT and OFFSET values. -1 means not used */
|
|
char *zSelect; /* Complete text of the SELECT command */
|
|
int base; /* Index of VDBE cursor for left-most FROM table */
|
|
};
|
|
|
|
/*
|
|
** The results of a select can be distributed in several ways.
|
|
*/
|
|
#define SRT_Callback 1 /* Invoke a callback with each row of result */
|
|
#define SRT_Mem 2 /* Store result in a memory cell */
|
|
#define SRT_Set 3 /* Store result as unique keys in a table */
|
|
#define SRT_Union 5 /* Store result as keys in a table */
|
|
#define SRT_Except 6 /* Remove result from a UNION table */
|
|
#define SRT_Table 7 /* Store result as data with a unique key */
|
|
#define SRT_TempTable 8 /* Store result in a trasient table */
|
|
#define SRT_Discard 9 /* Do not save the results anywhere */
|
|
|
|
/*
|
|
** When a SELECT uses aggregate functions (like "count(*)" or "avg(f1)")
|
|
** we have to do some additional analysis of expressions. An instance
|
|
** of the following structure holds information about a single subexpression
|
|
** somewhere in the SELECT statement. An array of these structures holds
|
|
** all the information we need to generate code for aggregate
|
|
** expressions.
|
|
**
|
|
** Note that when analyzing a SELECT containing aggregates, both
|
|
** non-aggregate field variables and aggregate functions are stored
|
|
** in the AggExpr array of the Parser structure.
|
|
**
|
|
** The pExpr field points to an expression that is part of either the
|
|
** field list, the GROUP BY clause, the HAVING clause or the ORDER BY
|
|
** clause. The expression will be freed when those clauses are cleaned
|
|
** up. Do not try to delete the expression attached to AggExpr.pExpr.
|
|
**
|
|
** If AggExpr.pExpr==0, that means the expression is "count(*)".
|
|
*/
|
|
struct AggExpr {
|
|
int isAgg; /* if TRUE contains an aggregate function */
|
|
Expr *pExpr; /* The expression */
|
|
FuncDef *pFunc; /* Information about the aggregate function */
|
|
};
|
|
|
|
/*
|
|
** An SQL parser context. A copy of this structure is passed through
|
|
** the parser and down into all the parser action routine in order to
|
|
** carry around information that is global to the entire parse.
|
|
*/
|
|
struct Parse {
|
|
sqlite *db; /* The main database structure */
|
|
Btree *pBe; /* The database backend */
|
|
int rc; /* Return code from execution */
|
|
sqlite_callback xCallback; /* The callback function */
|
|
void *pArg; /* First argument to the callback function */
|
|
char *zErrMsg; /* An error message */
|
|
Token sErrToken; /* The token at which the error occurred */
|
|
Token sFirstToken; /* The first token parsed */
|
|
Token sLastToken; /* The last token parsed */
|
|
Table *pNewTable; /* A table being constructed by CREATE TABLE */
|
|
Vdbe *pVdbe; /* An engine for executing database bytecode */
|
|
int colNamesSet; /* TRUE after OP_ColumnCount has been issued to pVdbe */
|
|
int explain; /* True if the EXPLAIN flag is found on the query */
|
|
int initFlag; /* True if reparsing CREATE TABLEs */
|
|
int nameClash; /* A permanent table name clashes with temp table name */
|
|
int newTnum; /* Table number to use when reparsing CREATE TABLEs */
|
|
int nErr; /* Number of errors seen */
|
|
int nTab; /* Number of previously allocated VDBE cursors */
|
|
int nMem; /* Number of memory cells used so far */
|
|
int nSet; /* Number of sets used so far */
|
|
int nAgg; /* Number of aggregate expressions */
|
|
AggExpr *aAgg; /* An array of aggregate expressions */
|
|
int useAgg; /* If true, extract field values from the aggregator
|
|
** while generating expressions. Normally false */
|
|
int schemaVerified; /* True if an OP_VerifySchema has been coded someplace
|
|
** other than after an OP_Transaction */
|
|
TriggerStack *trigStack;
|
|
};
|
|
|
|
/*
|
|
* Each trigger present in the database schema is stored as an instance of
|
|
* struct Trigger.
|
|
*
|
|
* Pointers to instances of struct Trigger are stored in two ways.
|
|
* 1. In the "trigHash" hash table (part of the sqlite* that represents the
|
|
* database). This allows Trigger structures to be retrieved by name.
|
|
* 2. All triggers associated with a single table form a linked list, using the
|
|
* pNext member of struct Trigger. A pointer to the first element of the
|
|
* linked list is stored as the "pTrigger" member of the associated
|
|
* struct Table.
|
|
*
|
|
* The "strings" member of struct Trigger contains a pointer to the memory
|
|
* referenced by the various Token structures referenced indirectly by the
|
|
* "pWhen", "pColumns" and "step_list" members. (ie. the memory allocated for
|
|
* use in conjunction with the sqliteExprMoveStrings() etc. interface).
|
|
*
|
|
* The "step_list" member points to the first element of a linked list
|
|
* containing the SQL statements specified as the trigger program.
|
|
*
|
|
* When a trigger is initially created, the "isCommit" member is set to FALSE.
|
|
* When a transaction is rolled back, any Trigger structures with "isCommit" set
|
|
* to FALSE are deleted by the logic in sqliteRollbackInternalChanges(). When
|
|
* a transaction is commited, the "isCommit" member is set to TRUE for any
|
|
* Trigger structures for which it is FALSE.
|
|
*
|
|
* When a trigger is dropped, using the sqliteDropTrigger() interfaced, it is
|
|
* removed from the trigHash hash table and added to the trigDrop hash table.
|
|
* If the transaction is rolled back, the trigger is re-added into the trigHash
|
|
* hash table (and hence the database schema). If the transaction is commited,
|
|
* then the Trigger structure is deleted permanently.
|
|
*/
|
|
struct Trigger {
|
|
char *name; /* The name of the trigger */
|
|
char *table; /* The table or view to which the trigger applies */
|
|
int op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT */
|
|
int tr_tm; /* One of TK_BEFORE, TK_AFTER */
|
|
Expr *pWhen; /* The WHEN clause of the expresion (may be NULL) */
|
|
IdList *pColumns; /* If this is an UPDATE OF <column-list> trigger,
|
|
the <column-list> is stored here */
|
|
int foreach; /* One of TK_ROW or TK_STATEMENT */
|
|
|
|
TriggerStep *step_list; /* Link list of trigger program steps */
|
|
char *strings; /* pointer to allocation of Token strings */
|
|
Trigger *pNext; /* Next trigger associated with the table */
|
|
int isCommit; /* Set to TRUE once the trigger has been committed */
|
|
};
|
|
|
|
/*
|
|
* An instance of struct TriggerStep is used to store a single SQL statement
|
|
* that is a part of a trigger-program.
|
|
*
|
|
* Instances of struct TriggerStep are stored in a singly linked list (linked
|
|
* using the "pNext" member) referenced by the "step_list" member of the
|
|
* associated struct Trigger instance. The first element of the linked list is
|
|
* the first step of the trigger-program.
|
|
*
|
|
* The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
|
|
* "SELECT" statement. The meanings of the other members is determined by the
|
|
* value of "op" as follows:
|
|
*
|
|
* (op == TK_INSERT)
|
|
* orconf -> stores the ON CONFLICT algorithm
|
|
* pSelect -> If this is an INSERT INTO ... SELECT ... statement, then
|
|
* this stores a pointer to the SELECT statement. Otherwise NULL.
|
|
* target -> A token holding the name of the table to insert into.
|
|
* pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
|
|
* this stores values to be inserted. Otherwise NULL.
|
|
* pIdList -> If this is an INSERT INTO ... (<column-names>) VALUES ...
|
|
* statement, then this stores the column-names to be
|
|
* inserted into.
|
|
*
|
|
* (op == TK_DELETE)
|
|
* target -> A token holding the name of the table to delete from.
|
|
* pWhere -> The WHERE clause of the DELETE statement if one is specified.
|
|
* Otherwise NULL.
|
|
*
|
|
* (op == TK_UPDATE)
|
|
* target -> A token holding the name of the table to update rows of.
|
|
* pWhere -> The WHERE clause of the UPDATE statement if one is specified.
|
|
* Otherwise NULL.
|
|
* pExprList -> A list of the columns to update and the expressions to update
|
|
* them to. See sqliteUpdate() documentation of "pChanges"
|
|
* argument.
|
|
*
|
|
*/
|
|
struct TriggerStep {
|
|
int op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
|
|
int orconf; /* OE_Rollback etc. */
|
|
|
|
Select *pSelect; /* Valid for SELECT and sometimes
|
|
INSERT steps (when pExprList == 0) */
|
|
Token target; /* Valid for DELETE, UPDATE, INSERT steps */
|
|
Expr *pWhere; /* Valid for DELETE, UPDATE steps */
|
|
ExprList *pExprList; /* Valid for UPDATE statements and sometimes
|
|
INSERT steps (when pSelect == 0) */
|
|
IdList *pIdList; /* Valid for INSERT statements only */
|
|
|
|
TriggerStep * pNext; /* Next in the link-list */
|
|
};
|
|
|
|
/*
|
|
* An instance of struct TriggerStack stores information required during code
|
|
* generation of a single trigger program. While the trigger program is being
|
|
* coded, its associated TriggerStack instance is pointed to by the
|
|
* "pTriggerStack" member of the Parse structure.
|
|
*
|
|
* The pTab member points to the table that triggers are being coded on. The
|
|
* newIdx member contains the index of the vdbe cursor that points at the temp
|
|
* table that stores the new.* references. If new.* references are not valid
|
|
* for the trigger being coded (for example an ON DELETE trigger), then newIdx
|
|
* is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
|
|
*
|
|
* The ON CONFLICT policy to be used for the trigger program steps is stored
|
|
* as the orconf member. If this is OE_Default, then the ON CONFLICT clause
|
|
* specified for individual triggers steps is used.
|
|
*
|
|
* struct TriggerStack has a "pNext" member, to allow linked lists to be
|
|
* constructed. When coding nested triggers (triggers fired by other triggers)
|
|
* each nested trigger stores its parent trigger's TriggerStack as the "pNext"
|
|
* pointer. Once the nested trigger has been coded, the pNext value is restored
|
|
* to the pTriggerStack member of the Parse stucture and coding of the parent
|
|
* trigger continues.
|
|
*
|
|
* Before a nested trigger is coded, the linked list pointed to by the
|
|
* pTriggerStack is scanned to ensure that the trigger is not about to be coded
|
|
* recursively. If this condition is detected, the nested trigger is not coded.
|
|
*/
|
|
struct TriggerStack {
|
|
Table *pTab; /* Table that triggers are currently being coded on */
|
|
int newIdx; /* Index of vdbe cursor to "new" temp table */
|
|
int oldIdx; /* Index of vdbe cursor to "old" temp table */
|
|
int orconf; /* Current orconf policy */
|
|
Trigger *pTrigger;
|
|
|
|
TriggerStack *pNext;
|
|
};
|
|
|
|
/*
|
|
* This global flag is set for performance testing of triggers. When it is set
|
|
* SQLite will perform the overhead of building new and old trigger references
|
|
* even when no triggers exist
|
|
*/
|
|
extern int always_code_trigger_setup;
|
|
|
|
/*
|
|
** Internal function prototypes
|
|
*/
|
|
int sqliteStrICmp(const char *, const char *);
|
|
int sqliteStrNICmp(const char *, const char *, int);
|
|
int sqliteHashNoCase(const char *, int);
|
|
int sqliteCompare(const char *, const char *);
|
|
int sqliteSortCompare(const char *, const char *);
|
|
void sqliteRealToSortable(double r, char *);
|
|
#ifdef MEMORY_DEBUG
|
|
void *sqliteMalloc_(int,char*,int);
|
|
void sqliteFree_(void*,char*,int);
|
|
void *sqliteRealloc_(void*,int,char*,int);
|
|
char *sqliteStrDup_(const char*,char*,int);
|
|
char *sqliteStrNDup_(const char*, int,char*,int);
|
|
#else
|
|
void *sqliteMalloc(int);
|
|
void sqliteFree(void*);
|
|
void *sqliteRealloc(void*,int);
|
|
char *sqliteStrDup(const char*);
|
|
char *sqliteStrNDup(const char*, int);
|
|
#endif
|
|
void sqliteSetString(char **, const char *, ...);
|
|
void sqliteSetNString(char **, ...);
|
|
void sqliteDequote(char*);
|
|
int sqliteKeywordCode(const char*, int);
|
|
int sqliteRunParser(Parse*, const char*, char **);
|
|
void sqliteExec(Parse*);
|
|
Expr *sqliteExpr(int, Expr*, Expr*, Token*);
|
|
void sqliteExprSpan(Expr*,Token*,Token*);
|
|
Expr *sqliteExprFunction(ExprList*, Token*);
|
|
void sqliteExprDelete(Expr*);
|
|
ExprList *sqliteExprListAppend(ExprList*,Expr*,Token*);
|
|
void sqliteExprListDelete(ExprList*);
|
|
void sqlitePragma(Parse*,Token*,Token*,int);
|
|
void sqliteCommitInternalChanges(sqlite*);
|
|
void sqliteRollbackInternalChanges(sqlite*);
|
|
Table *sqliteResultSetOfSelect(Parse*,char*,Select*);
|
|
void sqliteStartTable(Parse*,Token*,Token*,int);
|
|
void sqliteAddColumn(Parse*,Token*);
|
|
void sqliteAddNotNull(Parse*, int);
|
|
void sqliteAddPrimaryKey(Parse*, IdList*, int);
|
|
void sqliteAddColumnType(Parse*,Token*,Token*);
|
|
void sqliteAddDefaultValue(Parse*,Token*,int);
|
|
void sqliteEndTable(Parse*,Token*,Select*);
|
|
void sqliteCreateView(Parse*,Token*,Token*,Select*);
|
|
int sqliteViewGetColumnNames(Parse*,Table*);
|
|
void sqliteViewResetAll(sqlite*);
|
|
void sqliteDropTable(Parse*, Token*, int);
|
|
void sqliteDeleteTable(sqlite*, Table*);
|
|
void sqliteInsert(Parse*, Token*, ExprList*, Select*, IdList*, int);
|
|
IdList *sqliteIdListAppend(IdList*, Token*);
|
|
int sqliteIdListIndex(IdList*,const char*);
|
|
SrcList *sqliteSrcListAppend(SrcList*, Token*);
|
|
void sqliteSrcListAddAlias(SrcList*, Token*);
|
|
void sqliteIdListDelete(IdList*);
|
|
void sqliteSrcListDelete(SrcList*);
|
|
void sqliteCreateIndex(Parse*, Token*, Token*, IdList*, int, Token*, Token*);
|
|
void sqliteDropIndex(Parse*, Token*);
|
|
int sqliteSelect(Parse*, Select*, int, int, Select*, int, int*);
|
|
Select *sqliteSelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
|
|
int,int,int);
|
|
void sqliteSelectDelete(Select*);
|
|
void sqliteSelectUnbind(Select*);
|
|
Table *sqliteTableNameToTable(Parse*, const char*);
|
|
SrcList *sqliteTableTokenToSrcList(Parse*, Token*);
|
|
void sqliteDeleteFrom(Parse*, Token*, Expr*);
|
|
void sqliteUpdate(Parse*, Token*, ExprList*, Expr*, int);
|
|
WhereInfo *sqliteWhereBegin(Parse*, int, SrcList*, Expr*, int);
|
|
void sqliteWhereEnd(WhereInfo*);
|
|
void sqliteExprCode(Parse*, Expr*);
|
|
void sqliteExprIfTrue(Parse*, Expr*, int, int);
|
|
void sqliteExprIfFalse(Parse*, Expr*, int, int);
|
|
Table *sqliteFindTable(sqlite*,const char*);
|
|
Index *sqliteFindIndex(sqlite*,const char*);
|
|
void sqliteUnlinkAndDeleteIndex(sqlite*,Index*);
|
|
void sqliteCopy(Parse*, Token*, Token*, Token*, int);
|
|
void sqliteVacuum(Parse*, Token*);
|
|
int sqliteGlobCompare(const unsigned char*,const unsigned char*);
|
|
int sqliteLikeCompare(const unsigned char*,const unsigned char*);
|
|
char *sqliteTableNameFromToken(Token*);
|
|
int sqliteExprCheck(Parse*, Expr*, int, int*);
|
|
int sqliteExprCompare(Expr*, Expr*);
|
|
int sqliteFuncId(Token*);
|
|
int sqliteExprResolveIds(Parse*, int, SrcList*, ExprList*, Expr*);
|
|
int sqliteExprAnalyzeAggregates(Parse*, Expr*);
|
|
Vdbe *sqliteGetVdbe(Parse*);
|
|
int sqliteRandomByte(void);
|
|
int sqliteRandomInteger(void);
|
|
void sqliteBeginTransaction(Parse*, int);
|
|
void sqliteCommitTransaction(Parse*);
|
|
void sqliteRollbackTransaction(Parse*);
|
|
char *sqlite_mprintf(const char *, ...);
|
|
int sqliteExprIsConstant(Expr*);
|
|
int sqliteExprIsInteger(Expr*, int*);
|
|
void sqliteGenerateRowDelete(Vdbe*, Table*, int, int);
|
|
void sqliteGenerateRowIndexDelete(Vdbe*, Table*, int, char*);
|
|
void sqliteGenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int);
|
|
void sqliteCompleteInsertion(Parse*, Table*, int, char*, int, int);
|
|
void sqliteBeginWriteOperation(Parse*, int);
|
|
void sqliteEndWriteOperation(Parse*);
|
|
void sqliteExprMoveStrings(Expr*, int);
|
|
void sqliteExprListMoveStrings(ExprList*, int);
|
|
void sqliteSelectMoveStrings(Select*, int);
|
|
Expr *sqliteExprDup(Expr*);
|
|
ExprList *sqliteExprListDup(ExprList*);
|
|
SrcList *sqliteSrcListDup(SrcList*);
|
|
IdList *sqliteIdListDup(IdList*);
|
|
Select *sqliteSelectDup(Select*);
|
|
FuncDef *sqliteFindFunction(sqlite*,const char*,int,int,int);
|
|
void sqliteRegisterBuildinFunctions(sqlite*);
|
|
int sqliteSafetyOn(sqlite*);
|
|
int sqliteSafetyOff(sqlite*);
|
|
int sqliteSafetyCheck(sqlite*);
|
|
void sqliteChangeCookie(sqlite *);
|
|
void sqliteCreateTrigger(Parse*, Token*, int, int, IdList*, Token*,
|
|
int, Expr*, TriggerStep*, char const*,int);
|
|
void sqliteDropTrigger(Parse*, Token*, int);
|
|
int sqliteTriggersExist(Parse* , Trigger* , int , int , int, ExprList*);
|
|
int sqliteCodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, int);
|
|
void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
|
|
TriggerStep *sqliteTriggerSelectStep(Select*);
|
|
TriggerStep *sqliteTriggerInsertStep(Token*, IdList*, ExprList*, Select*, int);
|
|
TriggerStep *sqliteTriggerUpdateStep(Token*, ExprList*, Expr*, int);
|
|
TriggerStep *sqliteTriggerDeleteStep(Token*, Expr*);
|
|
void sqliteDeleteTrigger(Trigger*);
|
|
int sqliteJoinType(Parse*, Token*, Token*, Token*);
|