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drh75897232000-05-29 14:26:00 +00001/*
drhb19a2bc2001-09-16 00:13:26 +00002** 2001 September 15
drh75897232000-05-29 14:26:00 +00003**
drhb19a2bc2001-09-16 00:13:26 +00004** The author disclaims copyright to this source code. In place of
5** a legal notice, here is a blessing:
drh75897232000-05-29 14:26:00 +00006**
drhb19a2bc2001-09-16 00:13:26 +00007** May you do good and not evil.
8** May you find forgiveness for yourself and forgive others.
9** May you share freely, never taking more than you give.
drh75897232000-05-29 14:26:00 +000010**
11*************************************************************************
12** Internal interface definitions for SQLite.
13**
drhc8d30ac2002-04-12 10:08:59 +000014** @(#) $Id: sqliteInt.h,v 1.105 2002/04/12 10:08:59 drh Exp $
drh75897232000-05-29 14:26:00 +000015*/
16#include "sqlite.h"
drhbeae3192001-09-22 18:12:08 +000017#include "hash.h"
drh75897232000-05-29 14:26:00 +000018#include "vdbe.h"
19#include "parse.h"
drhbe0072d2001-09-13 14:46:09 +000020#include "btree.h"
drh75897232000-05-29 14:26:00 +000021#include <stdio.h>
22#include <stdlib.h>
23#include <string.h>
24#include <assert.h>
25
drh967e8b72000-06-21 13:59:10 +000026/*
drha1b351a2001-09-14 16:42:12 +000027** The maximum number of in-memory pages to use for the main database
28** table and for temporary tables.
29*/
drh603240c2002-03-05 01:11:12 +000030#define MAX_PAGES 2000
31#define TEMP_PAGES 500
drha1b351a2001-09-14 16:42:12 +000032
33/*
drh5a2c2c22001-11-21 02:21:11 +000034** Integers of known sizes. These typedefs might change for architectures
35** where the sizes very. Preprocessor macros are available so that the
36** types can be conveniently redefined at compile-type. Like this:
37**
38** cc '-DUINTPTR_TYPE=long long int' ...
drh41a2b482001-01-20 19:52:49 +000039*/
drh5a2c2c22001-11-21 02:21:11 +000040#ifndef UINT32_TYPE
41# define UINT32_TYPE unsigned int
42#endif
43#ifndef UINT16_TYPE
44# define UINT16_TYPE unsigned short int
45#endif
46#ifndef UINT8_TYPE
47# define UINT8_TYPE unsigned char
48#endif
49#ifndef INTPTR_TYPE
50# define INTPTR_TYPE int
51#endif
52typedef UINT32_TYPE u32; /* 4-byte unsigned integer */
53typedef UINT16_TYPE u16; /* 2-byte unsigned integer */
54typedef UINT8_TYPE u8; /* 1-byte unsigned integer */
55typedef INTPTR_TYPE ptr; /* Big enough to hold a pointer */
56typedef unsigned INTPTR_TYPE uptr; /* Big enough to hold a pointer */
57
58/*
59** This macro casts a pointer to an integer. Useful for doing
60** pointer arithmetic.
61*/
62#define Addr(X) ((uptr)X)
drh41a2b482001-01-20 19:52:49 +000063
64/*
drh872ff862001-09-15 14:43:39 +000065** The maximum number of bytes of data that can be put into a single
drh80ff32f2001-11-04 18:32:46 +000066** row of a single table. The upper bound on this limit is 16777215
67** bytes (or 16MB-1). We have arbitrarily set the limit to just 1MB
68** here because the overflow page chain is inefficient for really big
69** records and we want to discourage people from thinking that
70** multi-megabyte records are OK. If your needs are different, you can
71** change this define and recompile to increase or decrease the record
72** size.
drh872ff862001-09-15 14:43:39 +000073*/
drh80ff32f2001-11-04 18:32:46 +000074#define MAX_BYTES_PER_ROW 1048576
drh872ff862001-09-15 14:43:39 +000075
76/*
drh967e8b72000-06-21 13:59:10 +000077** If memory allocation problems are found, recompile with
78**
79** -DMEMORY_DEBUG=1
80**
81** to enable some sanity checking on malloc() and free(). To
82** check for memory leaks, recompile with
83**
84** -DMEMORY_DEBUG=2
85**
86** and a line of text will be written to standard error for
87** each malloc() and free(). This output can be analyzed
88** by an AWK script to determine if there are any leaks.
89*/
drhdcc581c2000-05-30 13:44:19 +000090#ifdef MEMORY_DEBUG
91# define sqliteMalloc(X) sqliteMalloc_(X,__FILE__,__LINE__)
92# define sqliteFree(X) sqliteFree_(X,__FILE__,__LINE__)
93# define sqliteRealloc(X,Y) sqliteRealloc_(X,Y,__FILE__,__LINE__)
drh6e142f52000-06-08 13:36:40 +000094# define sqliteStrDup(X) sqliteStrDup_(X,__FILE__,__LINE__)
95# define sqliteStrNDup(X,Y) sqliteStrNDup_(X,Y,__FILE__,__LINE__)
drhc3c2fc92000-05-31 22:58:39 +000096 void sqliteStrRealloc(char**);
97#else
98# define sqliteStrRealloc(X)
drhdcc581c2000-05-30 13:44:19 +000099#endif
100
drh75897232000-05-29 14:26:00 +0000101/*
drhdaffd0e2001-04-11 14:28:42 +0000102** This variable gets set if malloc() ever fails. After it gets set,
103** the SQLite library shuts down permanently.
104*/
105extern int sqlite_malloc_failed;
106
107/*
drh6e142f52000-06-08 13:36:40 +0000108** The following global variables are used for testing and debugging
drh8c82b352000-12-10 18:23:50 +0000109** only. They only work if MEMORY_DEBUG is defined.
drh6e142f52000-06-08 13:36:40 +0000110*/
111#ifdef MEMORY_DEBUG
drh8c82b352000-12-10 18:23:50 +0000112extern int sqlite_nMalloc; /* Number of sqliteMalloc() calls */
113extern int sqlite_nFree; /* Number of sqliteFree() calls */
114extern int sqlite_iMallocFail; /* Fail sqliteMalloc() after this many calls */
drh6e142f52000-06-08 13:36:40 +0000115#endif
116
117/*
drh75897232000-05-29 14:26:00 +0000118** Name of the master database table. The master database table
119** is a special table that holds the names and attributes of all
120** user tables and indices.
121*/
122#define MASTER_NAME "sqlite_master"
123
124/*
125** A convenience macro that returns the number of elements in
126** an array.
127*/
128#define ArraySize(X) (sizeof(X)/sizeof(X[0]))
129
130/*
131** Forward references to structures
132*/
drh7020f652000-06-03 18:06:52 +0000133typedef struct Column Column;
drh75897232000-05-29 14:26:00 +0000134typedef struct Table Table;
135typedef struct Index Index;
136typedef struct Instruction Instruction;
137typedef struct Expr Expr;
138typedef struct ExprList ExprList;
139typedef struct Parse Parse;
140typedef struct Token Token;
141typedef struct IdList IdList;
142typedef struct WhereInfo WhereInfo;
drh6b563442001-11-07 16:48:26 +0000143typedef struct WhereLevel WhereLevel;
drh9bb61fe2000-06-05 16:01:39 +0000144typedef struct Select Select;
drh22827922000-06-06 17:27:05 +0000145typedef struct AggExpr AggExpr;
drh0bce8352002-02-28 00:41:10 +0000146typedef struct FuncDef FuncDef;
drh75897232000-05-29 14:26:00 +0000147
148/*
149** Each database is an instance of the following structure
150*/
151struct sqlite {
drh5e00f6c2001-09-13 13:46:56 +0000152 Btree *pBe; /* The B*Tree backend */
drhf57b3392001-10-08 13:22:32 +0000153 Btree *pBeTemp; /* Backend for session temporary tables */
drh5e00f6c2001-09-13 13:46:56 +0000154 int flags; /* Miscellanous flags. See below */
155 int file_format; /* What file format version is this database? */
drh50e5dad2001-09-15 00:57:28 +0000156 int schema_cookie; /* Magic number that changes with the schema */
157 int next_cookie; /* Value of schema_cookie after commit */
drhcd61c282002-03-06 22:01:34 +0000158 int cache_size; /* Number of pages to use in the cache */
drh5e00f6c2001-09-13 13:46:56 +0000159 int nTable; /* Number of tables in the database */
160 void *pBusyArg; /* 1st Argument to the busy callback */
drh353f57e2000-08-02 12:26:28 +0000161 int (*xBusyCallback)(void *,const char*,int); /* The busy callback */
drhbeae3192001-09-22 18:12:08 +0000162 Hash tblHash; /* All tables indexed by name */
163 Hash idxHash; /* All (named) indices indexed by name */
drh74e24cd2002-01-09 03:19:59 +0000164 Hash tblDrop; /* Uncommitted DROP TABLEs */
165 Hash idxDrop; /* Uncommitted DROP INDEXs */
drh0bce8352002-02-28 00:41:10 +0000166 Hash aFunc; /* All functions that can be in SQL exprs */
drhaf9ff332002-01-16 21:00:27 +0000167 int lastRowid; /* ROWID of most recent insert */
drh5cf8e8c2002-02-19 22:42:05 +0000168 int priorNewRowid; /* Last randomly generated ROWID */
drh1c928532002-01-31 15:54:21 +0000169 int onError; /* Default conflict algorithm */
drhc8d30ac2002-04-12 10:08:59 +0000170 int nChange; /* Number of rows changed */
171 int recursionDepth; /* Number of nested calls to sqlite_exec() */
drh75897232000-05-29 14:26:00 +0000172};
173
174/*
drh967e8b72000-06-21 13:59:10 +0000175** Possible values for the sqlite.flags.
drh75897232000-05-29 14:26:00 +0000176*/
drh5e00f6c2001-09-13 13:46:56 +0000177#define SQLITE_VdbeTrace 0x00000001 /* True to trace VDBE execution */
178#define SQLITE_Initialized 0x00000002 /* True after initialization */
179#define SQLITE_Interrupt 0x00000004 /* Cancel current operation */
180#define SQLITE_InTrans 0x00000008 /* True if in a transaction */
181#define SQLITE_InternChanges 0x00000010 /* Uncommitted Hash table changes */
drh382c0242001-10-06 16:33:02 +0000182#define SQLITE_FullColNames 0x00000020 /* Show full column names on SELECT */
drh1bee3d72001-10-15 00:44:35 +0000183#define SQLITE_CountRows 0x00000040 /* Count rows changed by INSERT, */
184 /* DELETE, or UPDATE and return */
185 /* the count using a callback. */
drh6a535342001-10-19 16:44:56 +0000186#define SQLITE_NullCallback 0x00000080 /* Invoke the callback once if the */
187 /* result set is empty */
drhc3a64ba2001-11-22 00:01:27 +0000188#define SQLITE_ResultDetails 0x00000100 /* Details added to result set */
drh417be792002-03-03 18:59:40 +0000189#define SQLITE_UnresetViews 0x00000200 /* True if one or more views have */
190 /* defined column names */
drh58b95762000-06-02 01:17:37 +0000191
192/*
drh0bce8352002-02-28 00:41:10 +0000193** Each SQL function is defined by an instance of the following
194** structure. A pointer to this structure is stored in the sqlite.aFunc
drh8e0a2f92002-02-23 23:45:45 +0000195** hash table. When multiple functions have the same name, the hash table
196** points to a linked list of these structures.
drh28037572000-08-02 13:47:41 +0000197*/
drh0bce8352002-02-28 00:41:10 +0000198struct FuncDef {
drh1350b032002-02-27 19:00:20 +0000199 void (*xFunc)(sqlite_func*,int,const char**); /* Regular function */
drh56c0e922002-03-12 23:10:04 +0000200 void (*xStep)(sqlite_func*,int,const char**); /* Aggregate function step */
drh1350b032002-02-27 19:00:20 +0000201 void (*xFinalize)(sqlite_func*); /* Aggregate function finializer */
202 int nArg; /* Number of arguments */
203 void *pUserData; /* User data parameter */
drh0bce8352002-02-28 00:41:10 +0000204 FuncDef *pNext; /* Next function with same name */
drh8e0a2f92002-02-23 23:45:45 +0000205};
drh28037572000-08-02 13:47:41 +0000206
207/*
drh967e8b72000-06-21 13:59:10 +0000208** information about each column of an SQL table is held in an instance
drh7020f652000-06-03 18:06:52 +0000209** of this structure.
210*/
211struct Column {
drh967e8b72000-06-21 13:59:10 +0000212 char *zName; /* Name of this column */
213 char *zDflt; /* Default value of this column */
drh382c0242001-10-06 16:33:02 +0000214 char *zType; /* Data type for this column */
drh4a324312001-12-21 14:30:42 +0000215 u8 notNull; /* True if there is a NOT NULL constraint */
216 u8 isPrimKey; /* True if this column is an INTEGER PRIMARY KEY */
drh7020f652000-06-03 18:06:52 +0000217};
218
219/*
drh22f70c32002-02-18 01:17:00 +0000220** Each SQL table is represented in memory by an instance of the
221** following structure.
222**
223** Expr.zName is the name of the table. The case of the original
224** CREATE TABLE statement is stored, but case is not significant for
225** comparisons.
226**
227** Expr.nCol is the number of columns in this table. Expr.aCol is a
228** pointer to an array of Column structures, one for each column.
229**
230** If the table has an INTEGER PRIMARY KEY, then Expr.iPKey is the index of
231** the column that is that key. Otherwise Expr.iPKey is negative. Note
232** that the datatype of the PRIMARY KEY must be INTEGER for this field to
233** be set. An INTEGER PRIMARY KEY is used as the rowid for each row of
234** the table. If a table has no INTEGER PRIMARY KEY, then a random rowid
235** is generated for each row of the table. Expr.hasPrimKey is true if
236** the table has any PRIMARY KEY, INTEGER or otherwise.
237**
238** Expr.tnum is the page number for the root BTree page of the table in the
239** database file. If Expr.isTemp is true, then this page occurs in the
240** auxiliary database file, not the main database file. If Expr.isTransient
241** is true, then the table is stored in a file that is automatically deleted
242** when the VDBE cursor to the table is closed. In this case Expr.tnum
243** refers VDBE cursor number that holds the table open, not to the root
244** page number. Transient tables are used to hold the results of a
245** sub-query that appears instead of a real table name in the FROM clause
246** of a SELECT statement.
drh75897232000-05-29 14:26:00 +0000247*/
248struct Table {
drh967e8b72000-06-21 13:59:10 +0000249 char *zName; /* Name of the table */
drh967e8b72000-06-21 13:59:10 +0000250 int nCol; /* Number of columns in this table */
251 Column *aCol; /* Information about each column */
drhc8392582001-12-31 02:48:51 +0000252 int iPKey; /* If not less then 0, use aCol[iPKey] as the primary key */
drh967e8b72000-06-21 13:59:10 +0000253 Index *pIndex; /* List of SQL indexes on this table. */
drh22f70c32002-02-18 01:17:00 +0000254 int tnum; /* Root BTree node for this table (see note above) */
drha76b5df2002-02-23 02:32:10 +0000255 Select *pSelect; /* NULL for tables. Points to definition if a view. */
drh717e6402001-09-27 03:22:32 +0000256 u8 readOnly; /* True if this table should not be written by the user */
257 u8 isCommit; /* True if creation of this table has been committed */
drhf57b3392001-10-08 13:22:32 +0000258 u8 isTemp; /* True if stored in db->pBeTemp instead of db->pBe */
drh22f70c32002-02-18 01:17:00 +0000259 u8 isTransient; /* True if automatically deleted when VDBE finishes */
drh4a324312001-12-21 14:30:42 +0000260 u8 hasPrimKey; /* True if there exists a primary key */
drh9cfcf5d2002-01-29 18:41:24 +0000261 u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */
drh75897232000-05-29 14:26:00 +0000262};
263
264/*
drh22f70c32002-02-18 01:17:00 +0000265** SQLite supports 5 different ways to resolve a contraint
266** error. ROLLBACK processing means that a constraint violation
drh1c928532002-01-31 15:54:21 +0000267** causes the operation in proces to fail and for the current transaction
268** to be rolled back. ABORT processing means the operation in process
269** fails and any prior changes from that one operation are backed out,
270** but the transaction is not rolled back. FAIL processing means that
271** the operation in progress stops and returns an error code. But prior
272** changes due to the same operation are not backed out and no rollback
273** occurs. IGNORE means that the particular row that caused the constraint
274** error is not inserted or updated. Processing continues and no error
275** is returned. REPLACE means that preexisting database rows that caused
276** a UNIQUE constraint violation are removed so that the new insert or
277** update can proceed. Processing continues and no error is reported.
278**
279** The following there symbolic values are used to record which type
280** of action to take.
drh9cfcf5d2002-01-29 18:41:24 +0000281*/
drh1c928532002-01-31 15:54:21 +0000282#define OE_None 0 /* There is no constraint to check */
283#define OE_Rollback 1 /* Fail the operation and rollback the transaction */
284#define OE_Abort 2 /* Back out changes but do no rollback transaction */
285#define OE_Fail 3 /* Stop the operation but leave all prior changes */
286#define OE_Ignore 4 /* Ignore the error. Do not do the INSERT or UPDATE */
287#define OE_Replace 5 /* Delete existing record, then do INSERT or UPDATE */
288#define OE_Default 9 /* Do whatever the default action is */
drh9cfcf5d2002-01-29 18:41:24 +0000289
290/*
drh66b89c82000-11-28 20:47:17 +0000291** Each SQL index is represented in memory by an
drh75897232000-05-29 14:26:00 +0000292** instance of the following structure.
drh967e8b72000-06-21 13:59:10 +0000293**
294** The columns of the table that are to be indexed are described
295** by the aiColumn[] field of this structure. For example, suppose
296** we have the following table and index:
297**
298** CREATE TABLE Ex1(c1 int, c2 int, c3 text);
299** CREATE INDEX Ex2 ON Ex1(c3,c1);
300**
301** In the Table structure describing Ex1, nCol==3 because there are
302** three columns in the table. In the Index structure describing
303** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
304** The value of aiColumn is {2, 0}. aiColumn[0]==2 because the
305** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
306** The second column to be indexed (c1) has an index of 0 in
307** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
drh75897232000-05-29 14:26:00 +0000308*/
309struct Index {
drh967e8b72000-06-21 13:59:10 +0000310 char *zName; /* Name of this index */
drh967e8b72000-06-21 13:59:10 +0000311 int nColumn; /* Number of columns in the table used by this index */
312 int *aiColumn; /* Which columns are used by this index. 1st is 0 */
313 Table *pTable; /* The SQL table being indexed */
drhbe0072d2001-09-13 14:46:09 +0000314 int tnum; /* Page containing root of this index in database file */
drh9cfcf5d2002-01-29 18:41:24 +0000315 u8 isUnique; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
drh717e6402001-09-27 03:22:32 +0000316 u8 isCommit; /* True if creation of this index has been committed */
drh74e24cd2002-01-09 03:19:59 +0000317 u8 isDropped; /* True if a DROP INDEX has executed on this index */
drh9cfcf5d2002-01-29 18:41:24 +0000318 u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
drh967e8b72000-06-21 13:59:10 +0000319 Index *pNext; /* The next index associated with the same table */
drh75897232000-05-29 14:26:00 +0000320};
321
322/*
323** Each token coming out of the lexer is an instance of
324** this structure.
325*/
326struct Token {
drh80ff32f2001-11-04 18:32:46 +0000327 const char *z; /* Text of the token. Not NULL-terminated! */
328 int n; /* Number of characters in this token */
drh75897232000-05-29 14:26:00 +0000329};
330
331/*
332** Each node of an expression in the parse tree is an instance
drh22f70c32002-02-18 01:17:00 +0000333** of this structure.
334**
335** Expr.op is the opcode. The integer parser token codes are reused
336** as opcodes here. For example, the parser defines TK_GE to be an integer
337** code representing the ">=" operator. This same integer code is reused
338** to represent the greater-than-or-equal-to operator in the expression
339** tree.
340**
341** Expr.pRight and Expr.pLeft are subexpressions. Expr.pList is a list
342** of argument if the expression is a function.
343**
344** Expr.token is the operator token for this node. Expr.span is the complete
345** subexpression represented by this node and all its decendents. These
346** fields are used for error reporting and for reconstructing the text of
347** an expression to use as the column name in a SELECT statement.
348**
349** An expression of the form ID or ID.ID refers to a column in a table.
350** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
351** the integer cursor number of a VDBE cursor pointing to that table and
352** Expr.iColumn is the column number for the specific column. If the
353** expression is used as a result in an aggregate SELECT, then the
354** value is also stored in the Expr.iAgg column in the aggregate so that
355** it can be accessed after all aggregates are computed.
356**
357** If the expression is a function, the Expr.iTable is an integer code
358** representing which function.
359**
360** The Expr.pSelect field points to a SELECT statement. The SELECT might
361** be the right operand of an IN operator. Or, if a scalar SELECT appears
362** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
363** operand.
drh75897232000-05-29 14:26:00 +0000364*/
365struct Expr {
366 int op; /* Operation performed by this node */
367 Expr *pLeft, *pRight; /* Left and right subnodes */
368 ExprList *pList; /* A list of expressions used as a function argument */
369 Token token; /* An operand token */
drhe1b6a5b2000-07-29 13:06:59 +0000370 Token span; /* Complete text of the expression */
drh967e8b72000-06-21 13:59:10 +0000371 int iTable, iColumn; /* When op==TK_COLUMN, then this expr node means the
372 ** iColumn-th field of the iTable-th table. When
373 ** op==TK_FUNCTION, iColumn holds the function id */
374 int iAgg; /* When op==TK_COLUMN and pParse->useAgg==TRUE, pull
375 ** result from the iAgg-th element of the aggregator */
drh19a775c2000-06-05 18:54:46 +0000376 Select *pSelect; /* When the expression is a sub-select */
drh75897232000-05-29 14:26:00 +0000377};
378
379/*
380** A list of expressions. Each expression may optionally have a
381** name. An expr/name combination can be used in several ways, such
382** as the list of "expr AS ID" fields following a "SELECT" or in the
383** list of "ID = expr" items in an UPDATE. A list of expressions can
384** also be used as the argument to a function, in which case the azName
385** field is not used.
386*/
387struct ExprList {
388 int nExpr; /* Number of expressions on the list */
drh6d4abfb2001-10-22 02:58:08 +0000389 struct ExprList_item {
drh75897232000-05-29 14:26:00 +0000390 Expr *pExpr; /* The list of expressions */
391 char *zName; /* Token associated with this expression */
drhd8bc7082000-06-07 23:51:50 +0000392 char sortOrder; /* 1 for DESC or 0 for ASC */
393 char isAgg; /* True if this is an aggregate like count(*) */
394 char done; /* A flag to indicate when processing is finished */
drh75897232000-05-29 14:26:00 +0000395 } *a; /* One entry for each expression */
396};
397
398/*
399** A list of identifiers.
400*/
401struct IdList {
402 int nId; /* Number of identifiers on the list */
drh6d4abfb2001-10-22 02:58:08 +0000403 struct IdList_item {
drh75897232000-05-29 14:26:00 +0000404 char *zName; /* Text of the identifier. */
405 char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */
drh967e8b72000-06-21 13:59:10 +0000406 int idx; /* Index in some Table.aCol[] of a column named zName */
drhdaffd0e2001-04-11 14:28:42 +0000407 Table *pTab; /* An SQL table corresponding to zName */
408 Select *pSelect; /* A SELECT statement used in place of a table name */
drh75897232000-05-29 14:26:00 +0000409 } *a; /* One entry for each identifier on the list */
410};
411
412/*
drh6b563442001-11-07 16:48:26 +0000413** For each nested loop in a WHERE clause implementation, the WhereInfo
414** structure contains a single instance of this structure. This structure
415** is intended to be private the the where.c module and should not be
416** access or modified by other modules.
417*/
418struct WhereLevel {
419 int iMem; /* Memory cell used by this level */
420 Index *pIdx; /* Index used */
421 int iCur; /* Cursor number used for this index */
drh487ab3c2001-11-08 00:45:21 +0000422 int score; /* How well this indexed scored */
drh6b563442001-11-07 16:48:26 +0000423 int brk; /* Jump here to break out of the loop */
424 int cont; /* Jump here to continue with the next loop cycle */
425 int op, p1, p2; /* Opcode used to terminate the loop */
426};
427
428/*
drh75897232000-05-29 14:26:00 +0000429** The WHERE clause processing routine has two halves. The
430** first part does the start of the WHERE loop and the second
431** half does the tail of the WHERE loop. An instance of
432** this structure is returned by the first half and passed
433** into the second half to give some continuity.
434*/
435struct WhereInfo {
436 Parse *pParse;
drh19a775c2000-06-05 18:54:46 +0000437 IdList *pTabList; /* List of tables in the join */
438 int iContinue; /* Jump here to continue with next record */
439 int iBreak; /* Jump here to break out of the loop */
440 int base; /* Index of first Open opcode */
drh6b563442001-11-07 16:48:26 +0000441 int nLevel; /* Number of nested loop */
drh832508b2002-03-02 17:04:07 +0000442 int savedNTab; /* Value of pParse->nTab before WhereBegin() */
443 int peakNTab; /* Value of pParse->nTab after WhereBegin() */
drh6b563442001-11-07 16:48:26 +0000444 WhereLevel a[1]; /* Information about each nest loop in the WHERE */
drh75897232000-05-29 14:26:00 +0000445};
446
447/*
drh9bb61fe2000-06-05 16:01:39 +0000448** An instance of the following structure contains all information
449** needed to generate code for a single SELECT statement.
drha76b5df2002-02-23 02:32:10 +0000450**
451** The zSelect field is used when the Select structure must be persistent.
452** Normally, the expression tree points to tokens in the original input
453** string that encodes the select. But if the Select structure must live
454** longer than its input string (for example when it is used to describe
455** a VIEW) we have to make a copy of the input string so that the nodes
456** of the expression tree will have something to point to. zSelect is used
457** to hold that copy.
drh9bb61fe2000-06-05 16:01:39 +0000458*/
459struct Select {
460 int isDistinct; /* True if the DISTINCT keyword is present */
461 ExprList *pEList; /* The fields of the result */
462 IdList *pSrc; /* The FROM clause */
463 Expr *pWhere; /* The WHERE clause */
464 ExprList *pGroupBy; /* The GROUP BY clause */
465 Expr *pHaving; /* The HAVING clause */
466 ExprList *pOrderBy; /* The ORDER BY clause */
drh82c3d632000-06-06 21:56:07 +0000467 int op; /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
drh967e8b72000-06-21 13:59:10 +0000468 Select *pPrior; /* Prior select in a compound select statement */
drh9bbca4c2001-11-06 04:00:18 +0000469 int nLimit, nOffset; /* LIMIT and OFFSET values. -1 means not used */
drha76b5df2002-02-23 02:32:10 +0000470 char *zSelect; /* Complete text of the SELECT command */
drh832508b2002-03-02 17:04:07 +0000471 int base; /* Index of VDBE cursor for left-most FROM table */
drh9bb61fe2000-06-05 16:01:39 +0000472};
473
474/*
drhfef52082000-06-06 01:50:43 +0000475** The results of a select can be distributed in several ways.
476*/
477#define SRT_Callback 1 /* Invoke a callback with each row of result */
478#define SRT_Mem 2 /* Store result in a memory cell */
drh82c3d632000-06-06 21:56:07 +0000479#define SRT_Set 3 /* Store result as unique keys in a table */
480#define SRT_Union 5 /* Store result as keys in a table */
481#define SRT_Except 6 /* Remove result from a UNION table */
drh5974a302000-06-07 14:42:26 +0000482#define SRT_Table 7 /* Store result as data with a unique key */
drh2d0794e2002-03-03 03:03:52 +0000483#define SRT_TempTable 8 /* Store result in a trasient table */
drhfef52082000-06-06 01:50:43 +0000484
485/*
drh22827922000-06-06 17:27:05 +0000486** When a SELECT uses aggregate functions (like "count(*)" or "avg(f1)")
487** we have to do some additional analysis of expressions. An instance
488** of the following structure holds information about a single subexpression
489** somewhere in the SELECT statement. An array of these structures holds
490** all the information we need to generate code for aggregate
491** expressions.
492**
493** Note that when analyzing a SELECT containing aggregates, both
494** non-aggregate field variables and aggregate functions are stored
495** in the AggExpr array of the Parser structure.
496**
497** The pExpr field points to an expression that is part of either the
498** field list, the GROUP BY clause, the HAVING clause or the ORDER BY
499** clause. The expression will be freed when those clauses are cleaned
500** up. Do not try to delete the expression attached to AggExpr.pExpr.
501**
502** If AggExpr.pExpr==0, that means the expression is "count(*)".
503*/
504struct AggExpr {
505 int isAgg; /* if TRUE contains an aggregate function */
506 Expr *pExpr; /* The expression */
drh0bce8352002-02-28 00:41:10 +0000507 FuncDef *pFunc; /* Information about the aggregate function */
drh22827922000-06-06 17:27:05 +0000508};
509
510/*
drhf57b3392001-10-08 13:22:32 +0000511** An SQL parser context. A copy of this structure is passed through
512** the parser and down into all the parser action routine in order to
513** carry around information that is global to the entire parse.
drh75897232000-05-29 14:26:00 +0000514*/
515struct Parse {
516 sqlite *db; /* The main database structure */
drh5e00f6c2001-09-13 13:46:56 +0000517 Btree *pBe; /* The database backend */
drh4c504392000-10-16 22:06:40 +0000518 int rc; /* Return code from execution */
drh75897232000-05-29 14:26:00 +0000519 sqlite_callback xCallback; /* The callback function */
520 void *pArg; /* First argument to the callback function */
521 char *zErrMsg; /* An error message */
522 Token sErrToken; /* The token at which the error occurred */
523 Token sFirstToken; /* The first token parsed */
524 Token sLastToken; /* The last token parsed */
525 Table *pNewTable; /* A table being constructed by CREATE TABLE */
526 Vdbe *pVdbe; /* An engine for executing database bytecode */
drhd8bc7082000-06-07 23:51:50 +0000527 int colNamesSet; /* TRUE after OP_ColumnCount has been issued to pVdbe */
drh75897232000-05-29 14:26:00 +0000528 int explain; /* True if the EXPLAIN flag is found on the query */
529 int initFlag; /* True if reparsing CREATE TABLEs */
drhf57b3392001-10-08 13:22:32 +0000530 int nameClash; /* A permanent table name clashes with temp table name */
drhd78eeee2001-09-13 16:18:53 +0000531 int newTnum; /* Table number to use when reparsing CREATE TABLEs */
drh75897232000-05-29 14:26:00 +0000532 int nErr; /* Number of errors seen */
drh832508b2002-03-02 17:04:07 +0000533 int nTab; /* Number of previously allocated VDBE cursors */
drh19a775c2000-06-05 18:54:46 +0000534 int nMem; /* Number of memory cells used so far */
drhfef52082000-06-06 01:50:43 +0000535 int nSet; /* Number of sets used so far */
drh22827922000-06-06 17:27:05 +0000536 int nAgg; /* Number of aggregate expressions */
537 AggExpr *aAgg; /* An array of aggregate expressions */
drh22827922000-06-06 17:27:05 +0000538 int useAgg; /* If true, extract field values from the aggregator
539 ** while generating expressions. Normally false */
drh50e5dad2001-09-15 00:57:28 +0000540 int schemaVerified; /* True if an OP_VerifySchema has been coded someplace
541 ** other than after an OP_Transaction */
drh75897232000-05-29 14:26:00 +0000542};
543
544/*
545** Internal function prototypes
546*/
547int sqliteStrICmp(const char *, const char *);
548int sqliteStrNICmp(const char *, const char *, int);
549int sqliteHashNoCase(const char *, int);
550int sqliteCompare(const char *, const char *);
551int sqliteSortCompare(const char *, const char *);
drh9bbca4c2001-11-06 04:00:18 +0000552void sqliteRealToSortable(double r, char *);
drhdcc581c2000-05-30 13:44:19 +0000553#ifdef MEMORY_DEBUG
554 void *sqliteMalloc_(int,char*,int);
555 void sqliteFree_(void*,char*,int);
556 void *sqliteRealloc_(void*,int,char*,int);
drh6e142f52000-06-08 13:36:40 +0000557 char *sqliteStrDup_(const char*,char*,int);
558 char *sqliteStrNDup_(const char*, int,char*,int);
drhdcc581c2000-05-30 13:44:19 +0000559#else
560 void *sqliteMalloc(int);
561 void sqliteFree(void*);
562 void *sqliteRealloc(void*,int);
drh6e142f52000-06-08 13:36:40 +0000563 char *sqliteStrDup(const char*);
564 char *sqliteStrNDup(const char*, int);
drhdcc581c2000-05-30 13:44:19 +0000565#endif
drh75897232000-05-29 14:26:00 +0000566void sqliteSetString(char **, const char *, ...);
567void sqliteSetNString(char **, ...);
drh982cef72000-05-30 16:27:03 +0000568void sqliteDequote(char*);
drh17f71932002-02-21 12:01:27 +0000569int sqliteKeywordCode(const char*, int);
drh80ff32f2001-11-04 18:32:46 +0000570int sqliteRunParser(Parse*, const char*, char **);
drh75897232000-05-29 14:26:00 +0000571void sqliteExec(Parse*);
572Expr *sqliteExpr(int, Expr*, Expr*, Token*);
drhe1b6a5b2000-07-29 13:06:59 +0000573void sqliteExprSpan(Expr*,Token*,Token*);
drh75897232000-05-29 14:26:00 +0000574Expr *sqliteExprFunction(ExprList*, Token*);
575void sqliteExprDelete(Expr*);
576ExprList *sqliteExprListAppend(ExprList*,Expr*,Token*);
577void sqliteExprListDelete(ExprList*);
drhf57b14a2001-09-14 18:54:08 +0000578void sqlitePragma(Parse*,Token*,Token*,int);
drh5e00f6c2001-09-13 13:46:56 +0000579void sqliteCommitInternalChanges(sqlite*);
580void sqliteRollbackInternalChanges(sqlite*);
drh969fa7c2002-02-18 18:30:32 +0000581Table *sqliteResultSetOfSelect(Parse*,char*,Select*);
drhf57b3392001-10-08 13:22:32 +0000582void sqliteStartTable(Parse*,Token*,Token*,int);
drh75897232000-05-29 14:26:00 +0000583void sqliteAddColumn(Parse*,Token*);
drh9cfcf5d2002-01-29 18:41:24 +0000584void sqliteAddNotNull(Parse*, int);
585void sqliteAddPrimaryKey(Parse*, IdList*, int);
drh382c0242001-10-06 16:33:02 +0000586void sqliteAddColumnType(Parse*,Token*,Token*);
drh7020f652000-06-03 18:06:52 +0000587void sqliteAddDefaultValue(Parse*,Token*,int);
drh969fa7c2002-02-18 18:30:32 +0000588void sqliteEndTable(Parse*,Token*,Select*);
drha76b5df2002-02-23 02:32:10 +0000589void sqliteCreateView(Parse*,Token*,Token*,Select*);
drh417be792002-03-03 18:59:40 +0000590int sqliteViewGetColumnNames(Parse*,Table*);
591void sqliteViewResetAll(sqlite*);
drh4ff6dfa2002-03-03 23:06:00 +0000592void sqliteDropTable(Parse*, Token*, int);
drh75897232000-05-29 14:26:00 +0000593void sqliteDeleteTable(sqlite*, Table*);
drh9cfcf5d2002-01-29 18:41:24 +0000594void sqliteInsert(Parse*, Token*, ExprList*, Select*, IdList*, int);
drh75897232000-05-29 14:26:00 +0000595IdList *sqliteIdListAppend(IdList*, Token*);
596void sqliteIdListAddAlias(IdList*, Token*);
597void sqliteIdListDelete(IdList*);
drh717e6402001-09-27 03:22:32 +0000598void sqliteCreateIndex(Parse*, Token*, Token*, IdList*, int, Token*, Token*);
drh75897232000-05-29 14:26:00 +0000599void sqliteDropIndex(Parse*, Token*);
drh1b2e0322002-03-03 02:49:51 +0000600int sqliteSelect(Parse*, Select*, int, int, Select*, int, int*);
drh9bbca4c2001-11-06 04:00:18 +0000601Select *sqliteSelectNew(ExprList*,IdList*,Expr*,ExprList*,Expr*,ExprList*,
602 int,int,int);
drh9bb61fe2000-06-05 16:01:39 +0000603void sqliteSelectDelete(Select*);
drhff78bd22002-02-27 01:47:11 +0000604void sqliteSelectUnbind(Select*);
drha76b5df2002-02-23 02:32:10 +0000605Table *sqliteTableNameToTable(Parse*, const char*);
606IdList *sqliteTableTokenToIdList(Parse*, Token*);
drh75897232000-05-29 14:26:00 +0000607void sqliteDeleteFrom(Parse*, Token*, Expr*);
drh9cfcf5d2002-01-29 18:41:24 +0000608void sqliteUpdate(Parse*, Token*, ExprList*, Expr*, int);
drh832508b2002-03-02 17:04:07 +0000609WhereInfo *sqliteWhereBegin(Parse*, int, IdList*, Expr*, int);
drh75897232000-05-29 14:26:00 +0000610void sqliteWhereEnd(WhereInfo*);
611void sqliteExprCode(Parse*, Expr*);
612void sqliteExprIfTrue(Parse*, Expr*, int);
613void sqliteExprIfFalse(Parse*, Expr*, int);
drha76b5df2002-02-23 02:32:10 +0000614Table *sqliteFindTable(sqlite*,const char*);
615Index *sqliteFindIndex(sqlite*,const char*);
drh6d4abfb2001-10-22 02:58:08 +0000616void sqliteUnlinkAndDeleteIndex(sqlite*,Index*);
drhb419a922002-01-30 16:17:23 +0000617void sqliteCopy(Parse*, Token*, Token*, Token*, int);
drhdce2cbe2000-05-31 02:27:49 +0000618void sqliteVacuum(Parse*, Token*);
drhe17a7e32001-04-04 21:10:18 +0000619int sqliteGlobCompare(const unsigned char*,const unsigned char*);
drhdce2cbe2000-05-31 02:27:49 +0000620int sqliteLikeCompare(const unsigned char*,const unsigned char*);
drhcce7d172000-05-31 15:34:51 +0000621char *sqliteTableNameFromToken(Token*);
622int sqliteExprCheck(Parse*, Expr*, int, int*);
drhd8bc7082000-06-07 23:51:50 +0000623int sqliteExprCompare(Expr*, Expr*);
drhcce7d172000-05-31 15:34:51 +0000624int sqliteFuncId(Token*);
drh832508b2002-03-02 17:04:07 +0000625int sqliteExprResolveIds(Parse*, int, IdList*, ExprList*, Expr*);
drh22827922000-06-06 17:27:05 +0000626int sqliteExprAnalyzeAggregates(Parse*, Expr*);
drhd8bc7082000-06-07 23:51:50 +0000627Vdbe *sqliteGetVdbe(Parse*);
drhb8ca3072001-12-05 00:21:20 +0000628int sqliteRandomByte(void);
629int sqliteRandomInteger(void);
drh1c928532002-01-31 15:54:21 +0000630void sqliteBeginTransaction(Parse*, int);
drhc4a3c772001-04-04 11:48:57 +0000631void sqliteCommitTransaction(Parse*);
632void sqliteRollbackTransaction(Parse*);
drhd1bf3512001-04-07 15:24:33 +0000633char *sqlite_mprintf(const char *, ...);
drh92086432002-01-22 14:11:29 +0000634int sqliteExprIsConstant(Expr*);
drhc8d30ac2002-04-12 10:08:59 +0000635void sqliteGenerateRowDelete(Vdbe*, Table*, int, int);
drh0ca3e242002-01-29 23:07:02 +0000636void sqliteGenerateRowIndexDelete(Vdbe*, Table*, int, char*);
637void sqliteGenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int);
drhb419a922002-01-30 16:17:23 +0000638void sqliteCompleteInsertion(Parse*, Table*, int, char*, int, int);
drh1c928532002-01-31 15:54:21 +0000639void sqliteBeginWriteOperation(Parse*);
drh663fc632002-02-02 18:49:19 +0000640void sqliteBeginMultiWriteOperation(Parse*);
drh1c928532002-01-31 15:54:21 +0000641void sqliteEndWriteOperation(Parse*);
drha76b5df2002-02-23 02:32:10 +0000642void sqliteExprMoveStrings(Expr*, int);
643void sqliteExprListMoveStrings(ExprList*, int);
644void sqliteSelectMoveStrings(Select*, int);
drhff78bd22002-02-27 01:47:11 +0000645Expr *sqliteExprDup(Expr*);
646ExprList *sqliteExprListDup(ExprList*);
647IdList *sqliteIdListDup(IdList*);
648Select *sqliteSelectDup(Select*);
drh0bce8352002-02-28 00:41:10 +0000649FuncDef *sqliteFindFunction(sqlite*,const char*,int,int,int);
drhdc04c582002-02-24 01:55:15 +0000650void sqliteRegisterBuildinFunctions(sqlite*);