1 /*
2 ** 2001 September 15
3 **
4 ** The author disclaims copyright to this source code. In place of
5 ** a legal notice, here is a blessing:
6 **
7 ** 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.
10 **
11 *************************************************************************
12 ** This file contains C code routines that are called by the parser
13 ** to handle INSERT statements in SQLite.
14 **
15 ** $Id: insert.c,v 1.94 2004/02/24 01:05:33 drh Exp $
16 */
17 #include "sqliteInt.h"
18
19 /*
20 ** This routine is call to handle SQL of the following forms:
21 **
22 ** insert into TABLE (IDLIST) values(EXPRLIST)
23 ** insert into TABLE (IDLIST) select
24 **
25 ** The IDLIST following the table name is always optional. If omitted,
26 ** then a list of all columns for the table is substituted. The IDLIST
27 ** appears in the pColumn parameter. pColumn is NULL if IDLIST is omitted.
28 **
29 ** The pList parameter holds EXPRLIST in the first form of the INSERT
30 ** statement above, and pSelect is NULL. For the second form, pList is
31 ** NULL and pSelect is a pointer to the select statement used to generate
32 ** data for the insert.
33 **
34 ** The code generated follows one of three templates. For a simple
35 ** select with data coming from a VALUES clause, the code executes
36 ** once straight down through. The template looks like this:
37 **
38 ** open write cursor to <table> and its indices
39 ** puts VALUES clause expressions onto the stack
40 ** write the resulting record into <table>
41 ** cleanup
42 **
43 ** If the statement is of the form
44 **
45 ** INSERT INTO <table> SELECT ...
46 **
47 ** And the SELECT clause does not read from <table> at any time, then
48 ** the generated code follows this template:
49 **
50 ** goto B
51 ** A: setup for the SELECT
52 ** loop over the tables in the SELECT
53 ** gosub C
54 ** end loop
55 ** cleanup after the SELECT
56 ** goto D
57 ** B: open write cursor to <table> and its indices
58 ** goto A
59 ** C: insert the select result into <table>
60 ** return
61 ** D: cleanup
62 **
63 ** The third template is used if the insert statement takes its
64 ** values from a SELECT but the data is being inserted into a table
65 ** that is also read as part of the SELECT. In the third form,
66 ** we have to use a intermediate table to store the results of
67 ** the select. The template is like this:
68 **
69 ** goto B
70 ** A: setup for the SELECT
71 ** loop over the tables in the SELECT
72 ** gosub C
73 ** end loop
74 ** cleanup after the SELECT
75 ** goto D
76 ** C: insert the select result into the intermediate table
77 ** return
78 ** B: open a cursor to an intermediate table
79 ** goto A
80 ** D: open write cursor to <table> and its indices
81 ** loop over the intermediate table
82 ** transfer values form intermediate table into <table>
83 ** end the loop
84 ** cleanup
85 */
sqliteInsert(Parse * pParse,SrcList * pTabList,ExprList * pList,Select * pSelect,IdList * pColumn,int onError)86 void sqliteInsert(
87 Parse *pParse, /* Parser context */
88 SrcList *pTabList, /* Name of table into which we are inserting */
89 ExprList *pList, /* List of values to be inserted */
90 Select *pSelect, /* A SELECT statement to use as the data source */
91 IdList *pColumn, /* Column names corresponding to IDLIST. */
92 int onError /* How to handle constraint errors */
93 ){
94 Table *pTab; /* The table to insert into */
95 char *zTab; /* Name of the table into which we are inserting */
96 const char *zDb; /* Name of the database holding this table */
97 int i, j, idx; /* Loop counters */
98 Vdbe *v; /* Generate code into this virtual machine */
99 Index *pIdx; /* For looping over indices of the table */
100 int nColumn; /* Number of columns in the data */
101 int base; /* VDBE Cursor number for pTab */
102 int iCont, iBreak; /* Beginning and end of the loop over srcTab */
103 sqlite *db; /* The main database structure */
104 int keyColumn = -1; /* Column that is the INTEGER PRIMARY KEY */
105 int endOfLoop; /* Label for the end of the insertion loop */
106 int useTempTable; /* Store SELECT results in intermediate table */
107 int srcTab; /* Data comes from this temporary cursor if >=0 */
108 int iSelectLoop; /* Address of code that implements the SELECT */
109 int iCleanup; /* Address of the cleanup code */
110 int iInsertBlock; /* Address of the subroutine used to insert data */
111 int iCntMem; /* Memory cell used for the row counter */
112 int isView; /* True if attempting to insert into a view */
113
114 int row_triggers_exist = 0; /* True if there are FOR EACH ROW triggers */
115 int before_triggers; /* True if there are BEFORE triggers */
116 int after_triggers; /* True if there are AFTER triggers */
117 int newIdx = -1; /* Cursor for the NEW table */
118
119 if( pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
120 db = pParse->db;
121
122 /* Locate the table into which we will be inserting new information.
123 */
124 assert( pTabList->nSrc==1 );
125 zTab = pTabList->a[0].zName;
126 if( zTab==0 ) goto insert_cleanup;
127 pTab = sqliteSrcListLookup(pParse, pTabList);
128 if( pTab==0 ){
129 goto insert_cleanup;
130 }
131 assert( pTab->iDb<db->nDb );
132 zDb = db->aDb[pTab->iDb].zName;
133 if( sqliteAuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
134 goto insert_cleanup;
135 }
136
137 /* Ensure that:
138 * (a) the table is not read-only,
139 * (b) that if it is a view then ON INSERT triggers exist
140 */
141 before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
142 TK_BEFORE, TK_ROW, 0);
143 after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
144 TK_AFTER, TK_ROW, 0);
145 row_triggers_exist = before_triggers || after_triggers;
146 isView = pTab->pSelect!=0;
147 if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
148 goto insert_cleanup;
149 }
150 if( pTab==0 ) goto insert_cleanup;
151
152 /* If pTab is really a view, make sure it has been initialized.
153 */
154 if( isView && sqliteViewGetColumnNames(pParse, pTab) ){
155 goto insert_cleanup;
156 }
157
158 /* Allocate a VDBE
159 */
160 v = sqliteGetVdbe(pParse);
161 if( v==0 ) goto insert_cleanup;
162 sqliteBeginWriteOperation(pParse, pSelect || row_triggers_exist, pTab->iDb);
163
164 /* if there are row triggers, allocate a temp table for new.* references. */
165 if( row_triggers_exist ){
166 newIdx = pParse->nTab++;
167 }
168
169 /* Figure out how many columns of data are supplied. If the data
170 ** is coming from a SELECT statement, then this step also generates
171 ** all the code to implement the SELECT statement and invoke a subroutine
172 ** to process each row of the result. (Template 2.) If the SELECT
173 ** statement uses the the table that is being inserted into, then the
174 ** subroutine is also coded here. That subroutine stores the SELECT
175 ** results in a temporary table. (Template 3.)
176 */
177 if( pSelect ){
178 /* Data is coming from a SELECT. Generate code to implement that SELECT
179 */
180 int rc, iInitCode;
181 iInitCode = sqliteVdbeAddOp(v, OP_Goto, 0, 0);
182 iSelectLoop = sqliteVdbeCurrentAddr(v);
183 iInsertBlock = sqliteVdbeMakeLabel(v);
184 rc = sqliteSelect(pParse, pSelect, SRT_Subroutine, iInsertBlock, 0,0,0);
185 if( rc || pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
186 iCleanup = sqliteVdbeMakeLabel(v);
187 sqliteVdbeAddOp(v, OP_Goto, 0, iCleanup);
188 assert( pSelect->pEList );
189 nColumn = pSelect->pEList->nExpr;
190
191 /* Set useTempTable to TRUE if the result of the SELECT statement
192 ** should be written into a temporary table. Set to FALSE if each
193 ** row of the SELECT can be written directly into the result table.
194 **
195 ** A temp table must be used if the table being updated is also one
196 ** of the tables being read by the SELECT statement. Also use a
197 ** temp table in the case of row triggers.
198 */
199 if( row_triggers_exist ){
200 useTempTable = 1;
201 }else{
202 int addr = sqliteVdbeFindOp(v, OP_OpenRead, pTab->tnum);
203 useTempTable = 0;
204 if( addr>0 ){
205 VdbeOp *pOp = sqliteVdbeGetOp(v, addr-2);
206 if( pOp->opcode==OP_Integer && pOp->p1==pTab->iDb ){
207 useTempTable = 1;
208 }
209 }
210 }
211
212 if( useTempTable ){
213 /* Generate the subroutine that SELECT calls to process each row of
214 ** the result. Store the result in a temporary table
215 */
216 srcTab = pParse->nTab++;
217 sqliteVdbeResolveLabel(v, iInsertBlock);
218 sqliteVdbeAddOp(v, OP_MakeRecord, nColumn, 0);
219 sqliteVdbeAddOp(v, OP_NewRecno, srcTab, 0);
220 sqliteVdbeAddOp(v, OP_Pull, 1, 0);
221 sqliteVdbeAddOp(v, OP_PutIntKey, srcTab, 0);
222 sqliteVdbeAddOp(v, OP_Return, 0, 0);
223
224 /* The following code runs first because the GOTO at the very top
225 ** of the program jumps to it. Create the temporary table, then jump
226 ** back up and execute the SELECT code above.
227 */
228 sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
229 sqliteVdbeAddOp(v, OP_OpenTemp, srcTab, 0);
230 sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
231 sqliteVdbeResolveLabel(v, iCleanup);
232 }else{
233 sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
234 }
235 }else{
236 /* This is the case if the data for the INSERT is coming from a VALUES
237 ** clause
238 */
239 SrcList dummy;
240 assert( pList!=0 );
241 srcTab = -1;
242 useTempTable = 0;
243 assert( pList );
244 nColumn = pList->nExpr;
245 dummy.nSrc = 0;
246 for(i=0; i<nColumn; i++){
247 if( sqliteExprResolveIds(pParse, &dummy, 0, pList->a[i].pExpr) ){
248 goto insert_cleanup;
249 }
250 if( sqliteExprCheck(pParse, pList->a[i].pExpr, 0, 0) ){
251 goto insert_cleanup;
252 }
253 }
254 }
255
256 /* Make sure the number of columns in the source data matches the number
257 ** of columns to be inserted into the table.
258 */
259 if( pColumn==0 && nColumn!=pTab->nCol ){
260 sqliteErrorMsg(pParse,
261 "table %S has %d columns but %d values were supplied",
262 pTabList, 0, pTab->nCol, nColumn);
263 goto insert_cleanup;
264 }
265 if( pColumn!=0 && nColumn!=pColumn->nId ){
266 sqliteErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
267 goto insert_cleanup;
268 }
269
270 /* If the INSERT statement included an IDLIST term, then make sure
271 ** all elements of the IDLIST really are columns of the table and
272 ** remember the column indices.
273 **
274 ** If the table has an INTEGER PRIMARY KEY column and that column
275 ** is named in the IDLIST, then record in the keyColumn variable
276 ** the index into IDLIST of the primary key column. keyColumn is
277 ** the index of the primary key as it appears in IDLIST, not as
278 ** is appears in the original table. (The index of the primary
279 ** key in the original table is pTab->iPKey.)
280 */
281 if( pColumn ){
282 for(i=0; i<pColumn->nId; i++){
283 pColumn->a[i].idx = -1;
284 }
285 for(i=0; i<pColumn->nId; i++){
286 for(j=0; j<pTab->nCol; j++){
287 if( sqliteStrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
288 pColumn->a[i].idx = j;
289 if( j==pTab->iPKey ){
290 keyColumn = i;
291 }
292 break;
293 }
294 }
295 if( j>=pTab->nCol ){
296 if( sqliteIsRowid(pColumn->a[i].zName) ){
297 keyColumn = i;
298 }else{
299 sqliteErrorMsg(pParse, "table %S has no column named %s",
300 pTabList, 0, pColumn->a[i].zName);
301 pParse->nErr++;
302 goto insert_cleanup;
303 }
304 }
305 }
306 }
307
308 /* If there is no IDLIST term but the table has an integer primary
309 ** key, the set the keyColumn variable to the primary key column index
310 ** in the original table definition.
311 */
312 if( pColumn==0 ){
313 keyColumn = pTab->iPKey;
314 }
315
316 /* Open the temp table for FOR EACH ROW triggers
317 */
318 if( row_triggers_exist ){
319 sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
320 }
321
322 /* Initialize the count of rows to be inserted
323 */
324 if( db->flags & SQLITE_CountRows ){
325 iCntMem = pParse->nMem++;
326 sqliteVdbeAddOp(v, OP_Integer, 0, 0);
327 sqliteVdbeAddOp(v, OP_MemStore, iCntMem, 1);
328 }
329
330 /* Open tables and indices if there are no row triggers */
331 if( !row_triggers_exist ){
332 base = pParse->nTab;
333 idx = sqliteOpenTableAndIndices(pParse, pTab, base);
334 pParse->nTab += idx;
335 }
336
337 /* If the data source is a temporary table, then we have to create
338 ** a loop because there might be multiple rows of data. If the data
339 ** source is a subroutine call from the SELECT statement, then we need
340 ** to launch the SELECT statement processing.
341 */
342 if( useTempTable ){
343 iBreak = sqliteVdbeMakeLabel(v);
344 sqliteVdbeAddOp(v, OP_Rewind, srcTab, iBreak);
345 iCont = sqliteVdbeCurrentAddr(v);
346 }else if( pSelect ){
347 sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
348 sqliteVdbeResolveLabel(v, iInsertBlock);
349 }
350
351 /* Run the BEFORE and INSTEAD OF triggers, if there are any
352 */
353 endOfLoop = sqliteVdbeMakeLabel(v);
354 if( before_triggers ){
355
356 /* build the NEW.* reference row. Note that if there is an INTEGER
357 ** PRIMARY KEY into which a NULL is being inserted, that NULL will be
358 ** translated into a unique ID for the row. But on a BEFORE trigger,
359 ** we do not know what the unique ID will be (because the insert has
360 ** not happened yet) so we substitute a rowid of -1
361 */
362 if( keyColumn<0 ){
363 sqliteVdbeAddOp(v, OP_Integer, -1, 0);
364 }else if( useTempTable ){
365 sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
366 }else if( pSelect ){
367 sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
368 }else{
369 sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
370 sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
371 sqliteVdbeAddOp(v, OP_Pop, 1, 0);
372 sqliteVdbeAddOp(v, OP_Integer, -1, 0);
373 sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
374 }
375
376 /* Create the new column data
377 */
378 for(i=0; i<pTab->nCol; i++){
379 if( pColumn==0 ){
380 j = i;
381 }else{
382 for(j=0; j<pColumn->nId; j++){
383 if( pColumn->a[j].idx==i ) break;
384 }
385 }
386 if( pColumn && j>=pColumn->nId ){
387 sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
388 }else if( useTempTable ){
389 sqliteVdbeAddOp(v, OP_Column, srcTab, j);
390 }else if( pSelect ){
391 sqliteVdbeAddOp(v, OP_Dup, nColumn-j-1, 1);
392 }else{
393 sqliteExprCode(pParse, pList->a[j].pExpr);
394 }
395 }
396 sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
397 sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
398
399 /* Fire BEFORE or INSTEAD OF triggers */
400 if( sqliteCodeRowTrigger(pParse, TK_INSERT, 0, TK_BEFORE, pTab,
401 newIdx, -1, onError, endOfLoop) ){
402 goto insert_cleanup;
403 }
404 }
405
406 /* If any triggers exists, the opening of tables and indices is deferred
407 ** until now.
408 */
409 if( row_triggers_exist && !isView ){
410 base = pParse->nTab;
411 idx = sqliteOpenTableAndIndices(pParse, pTab, base);
412 pParse->nTab += idx;
413 }
414
415 /* Push the record number for the new entry onto the stack. The
416 ** record number is a randomly generate integer created by NewRecno
417 ** except when the table has an INTEGER PRIMARY KEY column, in which
418 ** case the record number is the same as that column.
419 */
420 if( !isView ){
421 if( keyColumn>=0 ){
422 if( useTempTable ){
423 sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
424 }else if( pSelect ){
425 sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
426 }else{
427 sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
428 }
429 /* If the PRIMARY KEY expression is NULL, then use OP_NewRecno
430 ** to generate a unique primary key value.
431 */
432 sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
433 sqliteVdbeAddOp(v, OP_Pop, 1, 0);
434 sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
435 sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
436 }else{
437 sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
438 }
439
440 /* Push onto the stack, data for all columns of the new entry, beginning
441 ** with the first column.
442 */
443 for(i=0; i<pTab->nCol; i++){
444 if( i==pTab->iPKey ){
445 /* The value of the INTEGER PRIMARY KEY column is always a NULL.
446 ** Whenever this column is read, the record number will be substituted
447 ** in its place. So will fill this column with a NULL to avoid
448 ** taking up data space with information that will never be used. */
449 sqliteVdbeAddOp(v, OP_String, 0, 0);
450 continue;
451 }
452 if( pColumn==0 ){
453 j = i;
454 }else{
455 for(j=0; j<pColumn->nId; j++){
456 if( pColumn->a[j].idx==i ) break;
457 }
458 }
459 if( pColumn && j>=pColumn->nId ){
460 sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
461 }else if( useTempTable ){
462 sqliteVdbeAddOp(v, OP_Column, srcTab, j);
463 }else if( pSelect ){
464 sqliteVdbeAddOp(v, OP_Dup, i+nColumn-j, 1);
465 }else{
466 sqliteExprCode(pParse, pList->a[j].pExpr);
467 }
468 }
469
470 /* Generate code to check constraints and generate index keys and
471 ** do the insertion.
472 */
473 sqliteGenerateConstraintChecks(pParse, pTab, base, 0, keyColumn>=0,
474 0, onError, endOfLoop);
475 sqliteCompleteInsertion(pParse, pTab, base, 0,0,0,
476 after_triggers ? newIdx : -1);
477 }
478
479 /* Update the count of rows that are inserted
480 */
481 if( (db->flags & SQLITE_CountRows)!=0 ){
482 sqliteVdbeAddOp(v, OP_MemIncr, iCntMem, 0);
483 }
484
485 if( row_triggers_exist ){
486 /* Close all tables opened */
487 if( !isView ){
488 sqliteVdbeAddOp(v, OP_Close, base, 0);
489 for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
490 sqliteVdbeAddOp(v, OP_Close, idx+base, 0);
491 }
492 }
493
494 /* Code AFTER triggers */
495 if( sqliteCodeRowTrigger(pParse, TK_INSERT, 0, TK_AFTER, pTab, newIdx, -1,
496 onError, endOfLoop) ){
497 goto insert_cleanup;
498 }
499 }
500
501 /* The bottom of the loop, if the data source is a SELECT statement
502 */
503 sqliteVdbeResolveLabel(v, endOfLoop);
504 if( useTempTable ){
505 sqliteVdbeAddOp(v, OP_Next, srcTab, iCont);
506 sqliteVdbeResolveLabel(v, iBreak);
507 sqliteVdbeAddOp(v, OP_Close, srcTab, 0);
508 }else if( pSelect ){
509 sqliteVdbeAddOp(v, OP_Pop, nColumn, 0);
510 sqliteVdbeAddOp(v, OP_Return, 0, 0);
511 sqliteVdbeResolveLabel(v, iCleanup);
512 }
513
514 if( !row_triggers_exist ){
515 /* Close all tables opened */
516 sqliteVdbeAddOp(v, OP_Close, base, 0);
517 for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
518 sqliteVdbeAddOp(v, OP_Close, idx+base, 0);
519 }
520 }
521
522 sqliteVdbeAddOp(v, OP_SetCounts, 0, 0);
523 sqliteEndWriteOperation(pParse);
524
525 /*
526 ** Return the number of rows inserted.
527 */
528 if( db->flags & SQLITE_CountRows ){
529 sqliteVdbeOp3(v, OP_ColumnName, 0, 1, "rows inserted", P3_STATIC);
530 sqliteVdbeAddOp(v, OP_MemLoad, iCntMem, 0);
531 sqliteVdbeAddOp(v, OP_Callback, 1, 0);
532 }
533
534 insert_cleanup:
535 sqliteSrcListDelete(pTabList);
536 if( pList ) sqliteExprListDelete(pList);
537 if( pSelect ) sqliteSelectDelete(pSelect);
538 sqliteIdListDelete(pColumn);
539 }
540
541 /*
542 ** Generate code to do a constraint check prior to an INSERT or an UPDATE.
543 **
544 ** When this routine is called, the stack contains (from bottom to top)
545 ** the following values:
546 **
547 ** 1. The recno of the row to be updated before the update. This
548 ** value is omitted unless we are doing an UPDATE that involves a
549 ** change to the record number.
550 **
551 ** 2. The recno of the row after the update.
552 **
553 ** 3. The data in the first column of the entry after the update.
554 **
555 ** i. Data from middle columns...
556 **
557 ** N. The data in the last column of the entry after the update.
558 **
559 ** The old recno shown as entry (1) above is omitted unless both isUpdate
560 ** and recnoChng are 1. isUpdate is true for UPDATEs and false for
561 ** INSERTs and recnoChng is true if the record number is being changed.
562 **
563 ** The code generated by this routine pushes additional entries onto
564 ** the stack which are the keys for new index entries for the new record.
565 ** The order of index keys is the same as the order of the indices on
566 ** the pTable->pIndex list. A key is only created for index i if
567 ** aIdxUsed!=0 and aIdxUsed[i]!=0.
568 **
569 ** This routine also generates code to check constraints. NOT NULL,
570 ** CHECK, and UNIQUE constraints are all checked. If a constraint fails,
571 ** then the appropriate action is performed. There are five possible
572 ** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
573 **
574 ** Constraint type Action What Happens
575 ** --------------- ---------- ----------------------------------------
576 ** any ROLLBACK The current transaction is rolled back and
577 ** sqlite_exec() returns immediately with a
578 ** return code of SQLITE_CONSTRAINT.
579 **
580 ** any ABORT Back out changes from the current command
581 ** only (do not do a complete rollback) then
582 ** cause sqlite_exec() to return immediately
583 ** with SQLITE_CONSTRAINT.
584 **
585 ** any FAIL Sqlite_exec() returns immediately with a
586 ** return code of SQLITE_CONSTRAINT. The
587 ** transaction is not rolled back and any
588 ** prior changes are retained.
589 **
590 ** any IGNORE The record number and data is popped from
591 ** the stack and there is an immediate jump
592 ** to label ignoreDest.
593 **
594 ** NOT NULL REPLACE The NULL value is replace by the default
595 ** value for that column. If the default value
596 ** is NULL, the action is the same as ABORT.
597 **
598 ** UNIQUE REPLACE The other row that conflicts with the row
599 ** being inserted is removed.
600 **
601 ** CHECK REPLACE Illegal. The results in an exception.
602 **
603 ** Which action to take is determined by the overrideError parameter.
604 ** Or if overrideError==OE_Default, then the pParse->onError parameter
605 ** is used. Or if pParse->onError==OE_Default then the onError value
606 ** for the constraint is used.
607 **
608 ** The calling routine must open a read/write cursor for pTab with
609 ** cursor number "base". All indices of pTab must also have open
610 ** read/write cursors with cursor number base+i for the i-th cursor.
611 ** Except, if there is no possibility of a REPLACE action then
612 ** cursors do not need to be open for indices where aIdxUsed[i]==0.
613 **
614 ** If the isUpdate flag is true, it means that the "base" cursor is
615 ** initially pointing to an entry that is being updated. The isUpdate
616 ** flag causes extra code to be generated so that the "base" cursor
617 ** is still pointing at the same entry after the routine returns.
618 ** Without the isUpdate flag, the "base" cursor might be moved.
619 */
sqliteGenerateConstraintChecks(Parse * pParse,Table * pTab,int base,char * aIdxUsed,int recnoChng,int isUpdate,int overrideError,int ignoreDest)620 void sqliteGenerateConstraintChecks(
621 Parse *pParse, /* The parser context */
622 Table *pTab, /* the table into which we are inserting */
623 int base, /* Index of a read/write cursor pointing at pTab */
624 char *aIdxUsed, /* Which indices are used. NULL means all are used */
625 int recnoChng, /* True if the record number will change */
626 int isUpdate, /* True for UPDATE, False for INSERT */
627 int overrideError, /* Override onError to this if not OE_Default */
628 int ignoreDest /* Jump to this label on an OE_Ignore resolution */
629 ){
630 int i;
631 Vdbe *v;
632 int nCol;
633 int onError;
634 int addr;
635 int extra;
636 int iCur;
637 Index *pIdx;
638 int seenReplace = 0;
639 int jumpInst1, jumpInst2;
640 int contAddr;
641 int hasTwoRecnos = (isUpdate && recnoChng);
642
643 v = sqliteGetVdbe(pParse);
644 assert( v!=0 );
645 assert( pTab->pSelect==0 ); /* This table is not a VIEW */
646 nCol = pTab->nCol;
647
648 /* Test all NOT NULL constraints.
649 */
650 for(i=0; i<nCol; i++){
651 if( i==pTab->iPKey ){
652 continue;
653 }
654 onError = pTab->aCol[i].notNull;
655 if( onError==OE_None ) continue;
656 if( overrideError!=OE_Default ){
657 onError = overrideError;
658 }else if( pParse->db->onError!=OE_Default ){
659 onError = pParse->db->onError;
660 }else if( onError==OE_Default ){
661 onError = OE_Abort;
662 }
663 if( onError==OE_Replace && pTab->aCol[i].zDflt==0 ){
664 onError = OE_Abort;
665 }
666 sqliteVdbeAddOp(v, OP_Dup, nCol-1-i, 1);
667 addr = sqliteVdbeAddOp(v, OP_NotNull, 1, 0);
668 switch( onError ){
669 case OE_Rollback:
670 case OE_Abort:
671 case OE_Fail: {
672 char *zMsg = 0;
673 sqliteVdbeAddOp(v, OP_Halt, SQLITE_CONSTRAINT, onError);
674 sqliteSetString(&zMsg, pTab->zName, ".", pTab->aCol[i].zName,
675 " may not be NULL", (char*)0);
676 sqliteVdbeChangeP3(v, -1, zMsg, P3_DYNAMIC);
677 break;
678 }
679 case OE_Ignore: {
680 sqliteVdbeAddOp(v, OP_Pop, nCol+1+hasTwoRecnos, 0);
681 sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
682 break;
683 }
684 case OE_Replace: {
685 sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
686 sqliteVdbeAddOp(v, OP_Push, nCol-i, 0);
687 break;
688 }
689 default: assert(0);
690 }
691 sqliteVdbeChangeP2(v, addr, sqliteVdbeCurrentAddr(v));
692 }
693
694 /* Test all CHECK constraints
695 */
696 /**** TBD ****/
697
698 /* If we have an INTEGER PRIMARY KEY, make sure the primary key
699 ** of the new record does not previously exist. Except, if this
700 ** is an UPDATE and the primary key is not changing, that is OK.
701 */
702 if( recnoChng ){
703 onError = pTab->keyConf;
704 if( overrideError!=OE_Default ){
705 onError = overrideError;
706 }else if( pParse->db->onError!=OE_Default ){
707 onError = pParse->db->onError;
708 }else if( onError==OE_Default ){
709 onError = OE_Abort;
710 }
711
712 if( isUpdate ){
713 sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
714 sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
715 jumpInst1 = sqliteVdbeAddOp(v, OP_Eq, 0, 0);
716 }
717 sqliteVdbeAddOp(v, OP_Dup, nCol, 1);
718 jumpInst2 = sqliteVdbeAddOp(v, OP_NotExists, base, 0);
719 switch( onError ){
720 default: {
721 onError = OE_Abort;
722 }
723 /* FALLTHROUGH */
724 case OE_Rollback:
725 case OE_Abort:
726 case OE_Fail: {
727 sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, onError,
728 "PRIMARY KEY must be unique", P3_STATIC);
729 break;
730 }
731 case OE_Replace: {
732 sqliteGenerateRowIndexDelete(pParse->db, v, pTab, base, 0);
733 if( isUpdate ){
734 sqliteVdbeAddOp(v, OP_Dup, nCol+hasTwoRecnos, 1);
735 sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
736 }
737 seenReplace = 1;
738 break;
739 }
740 case OE_Ignore: {
741 assert( seenReplace==0 );
742 sqliteVdbeAddOp(v, OP_Pop, nCol+1+hasTwoRecnos, 0);
743 sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
744 break;
745 }
746 }
747 contAddr = sqliteVdbeCurrentAddr(v);
748 sqliteVdbeChangeP2(v, jumpInst2, contAddr);
749 if( isUpdate ){
750 sqliteVdbeChangeP2(v, jumpInst1, contAddr);
751 sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
752 sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
753 }
754 }
755
756 /* Test all UNIQUE constraints by creating entries for each UNIQUE
757 ** index and making sure that duplicate entries do not already exist.
758 ** Add the new records to the indices as we go.
759 */
760 extra = -1;
761 for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
762 if( aIdxUsed && aIdxUsed[iCur]==0 ) continue; /* Skip unused indices */
763 extra++;
764
765 /* Create a key for accessing the index entry */
766 sqliteVdbeAddOp(v, OP_Dup, nCol+extra, 1);
767 for(i=0; i<pIdx->nColumn; i++){
768 int idx = pIdx->aiColumn[i];
769 if( idx==pTab->iPKey ){
770 sqliteVdbeAddOp(v, OP_Dup, i+extra+nCol+1, 1);
771 }else{
772 sqliteVdbeAddOp(v, OP_Dup, i+extra+nCol-idx, 1);
773 }
774 }
775 jumpInst1 = sqliteVdbeAddOp(v, OP_MakeIdxKey, pIdx->nColumn, 0);
776 if( pParse->db->file_format>=4 ) sqliteAddIdxKeyType(v, pIdx);
777
778 /* Find out what action to take in case there is an indexing conflict */
779 onError = pIdx->onError;
780 if( onError==OE_None ) continue; /* pIdx is not a UNIQUE index */
781 if( overrideError!=OE_Default ){
782 onError = overrideError;
783 }else if( pParse->db->onError!=OE_Default ){
784 onError = pParse->db->onError;
785 }else if( onError==OE_Default ){
786 onError = OE_Abort;
787 }
788 if( seenReplace ){
789 if( onError==OE_Ignore ) onError = OE_Replace;
790 else if( onError==OE_Fail ) onError = OE_Abort;
791 }
792
793
794 /* Check to see if the new index entry will be unique */
795 sqliteVdbeAddOp(v, OP_Dup, extra+nCol+1+hasTwoRecnos, 1);
796 jumpInst2 = sqliteVdbeAddOp(v, OP_IsUnique, base+iCur+1, 0);
797
798 /* Generate code that executes if the new index entry is not unique */
799 switch( onError ){
800 case OE_Rollback:
801 case OE_Abort:
802 case OE_Fail: {
803 int j, n1, n2;
804 char zErrMsg[200];
805 strcpy(zErrMsg, pIdx->nColumn>1 ? "columns " : "column ");
806 n1 = strlen(zErrMsg);
807 for(j=0; j<pIdx->nColumn && n1<sizeof(zErrMsg)-30; j++){
808 char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;
809 n2 = strlen(zCol);
810 if( j>0 ){
811 strcpy(&zErrMsg[n1], ", ");
812 n1 += 2;
813 }
814 if( n1+n2>sizeof(zErrMsg)-30 ){
815 strcpy(&zErrMsg[n1], "...");
816 n1 += 3;
817 break;
818 }else{
819 strcpy(&zErrMsg[n1], zCol);
820 n1 += n2;
821 }
822 }
823 strcpy(&zErrMsg[n1],
824 pIdx->nColumn>1 ? " are not unique" : " is not unique");
825 sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, onError, zErrMsg, 0);
826 break;
827 }
828 case OE_Ignore: {
829 assert( seenReplace==0 );
830 sqliteVdbeAddOp(v, OP_Pop, nCol+extra+3+hasTwoRecnos, 0);
831 sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
832 break;
833 }
834 case OE_Replace: {
835 sqliteGenerateRowDelete(pParse->db, v, pTab, base, 0);
836 if( isUpdate ){
837 sqliteVdbeAddOp(v, OP_Dup, nCol+extra+1+hasTwoRecnos, 1);
838 sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
839 }
840 seenReplace = 1;
841 break;
842 }
843 default: assert(0);
844 }
845 contAddr = sqliteVdbeCurrentAddr(v);
846 #if NULL_DISTINCT_FOR_UNIQUE
847 sqliteVdbeChangeP2(v, jumpInst1, contAddr);
848 #endif
849 sqliteVdbeChangeP2(v, jumpInst2, contAddr);
850 }
851 }
852
853 /*
854 ** This routine generates code to finish the INSERT or UPDATE operation
855 ** that was started by a prior call to sqliteGenerateConstraintChecks.
856 ** The stack must contain keys for all active indices followed by data
857 ** and the recno for the new entry. This routine creates the new
858 ** entries in all indices and in the main table.
859 **
860 ** The arguments to this routine should be the same as the first six
861 ** arguments to sqliteGenerateConstraintChecks.
862 */
sqliteCompleteInsertion(Parse * pParse,Table * pTab,int base,char * aIdxUsed,int recnoChng,int isUpdate,int newIdx)863 void sqliteCompleteInsertion(
864 Parse *pParse, /* The parser context */
865 Table *pTab, /* the table into which we are inserting */
866 int base, /* Index of a read/write cursor pointing at pTab */
867 char *aIdxUsed, /* Which indices are used. NULL means all are used */
868 int recnoChng, /* True if the record number will change */
869 int isUpdate, /* True for UPDATE, False for INSERT */
870 int newIdx /* Index of NEW table for triggers. -1 if none */
871 ){
872 int i;
873 Vdbe *v;
874 int nIdx;
875 Index *pIdx;
876
877 v = sqliteGetVdbe(pParse);
878 assert( v!=0 );
879 assert( pTab->pSelect==0 ); /* This table is not a VIEW */
880 for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
881 for(i=nIdx-1; i>=0; i--){
882 if( aIdxUsed && aIdxUsed[i]==0 ) continue;
883 sqliteVdbeAddOp(v, OP_IdxPut, base+i+1, 0);
884 }
885 sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
886 if( newIdx>=0 ){
887 sqliteVdbeAddOp(v, OP_Dup, 1, 0);
888 sqliteVdbeAddOp(v, OP_Dup, 1, 0);
889 sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
890 }
891 sqliteVdbeAddOp(v, OP_PutIntKey, base,
892 (pParse->trigStack?0:OPFLAG_NCHANGE) |
893 (isUpdate?0:OPFLAG_LASTROWID) | OPFLAG_CSCHANGE);
894 if( isUpdate && recnoChng ){
895 sqliteVdbeAddOp(v, OP_Pop, 1, 0);
896 }
897 }
898
899 /*
900 ** Generate code that will open write cursors for a table and for all
901 ** indices of that table. The "base" parameter is the cursor number used
902 ** for the table. Indices are opened on subsequent cursors.
903 **
904 ** Return the total number of cursors opened. This is always at least
905 ** 1 (for the main table) plus more for each cursor.
906 */
sqliteOpenTableAndIndices(Parse * pParse,Table * pTab,int base)907 int sqliteOpenTableAndIndices(Parse *pParse, Table *pTab, int base){
908 int i;
909 Index *pIdx;
910 Vdbe *v = sqliteGetVdbe(pParse);
911 assert( v!=0 );
912 sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
913 sqliteVdbeOp3(v, OP_OpenWrite, base, pTab->tnum, pTab->zName, P3_STATIC);
914 for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
915 sqliteVdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
916 sqliteVdbeOp3(v, OP_OpenWrite, i+base, pIdx->tnum, pIdx->zName, P3_STATIC);
917 }
918 return i;
919 }
920