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|
/*
** 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.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c 326789 2004-07-07 21:25:56Z pahlibar $
*/
#include "sqliteInt.h"
/*
** This routine is call to handle SQL of the following forms:
**
** insert into TABLE (IDLIST) values(EXPRLIST)
** insert into TABLE (IDLIST) select
**
** The IDLIST following the table name is always optional. If omitted,
** then a list of all columns for the table is substituted. The IDLIST
** appears in the pColumn parameter. pColumn is NULL if IDLIST is omitted.
**
** The pList parameter holds EXPRLIST in the first form of the INSERT
** statement above, and pSelect is NULL. For the second form, pList is
** NULL and pSelect is a pointer to the select statement used to generate
** data for the insert.
**
** The code generated follows one of three templates. For a simple
** select with data coming from a VALUES clause, the code executes
** once straight down through. The template looks like this:
**
** open write cursor to <table> and its indices
** puts VALUES clause expressions onto the stack
** write the resulting record into <table>
** cleanup
**
** If the statement is of the form
**
** INSERT INTO <table> SELECT ...
**
** And the SELECT clause does not read from <table> at any time, then
** the generated code follows this template:
**
** goto B
** A: setup for the SELECT
** loop over the tables in the SELECT
** gosub C
** end loop
** cleanup after the SELECT
** goto D
** B: open write cursor to <table> and its indices
** goto A
** C: insert the select result into <table>
** return
** D: cleanup
**
** The third template is used if the insert statement takes its
** values from a SELECT but the data is being inserted into a table
** that is also read as part of the SELECT. In the third form,
** we have to use a intermediate table to store the results of
** the select. The template is like this:
**
** goto B
** A: setup for the SELECT
** loop over the tables in the SELECT
** gosub C
** end loop
** cleanup after the SELECT
** goto D
** C: insert the select result into the intermediate table
** return
** B: open a cursor to an intermediate table
** goto A
** D: open write cursor to <table> and its indices
** loop over the intermediate table
** transfer values form intermediate table into <table>
** end the loop
** cleanup
*/
void sqliteInsert(
Parse *pParse, /* Parser context */
SrcList *pTabList, /* Name of table into which we are inserting */
ExprList *pList, /* List of values to be inserted */
Select *pSelect, /* A SELECT statement to use as the data source */
IdList *pColumn, /* Column names corresponding to IDLIST. */
int onError /* How to handle constraint errors */
){
Table *pTab; /* The table to insert into */
char *zTab; /* Name of the table into which we are inserting */
const char *zDb; /* Name of the database holding this table */
int i, j, idx; /* Loop counters */
Vdbe *v; /* Generate code into this virtual machine */
Index *pIdx; /* For looping over indices of the table */
int nColumn; /* Number of columns in the data */
int base; /* VDBE Cursor number for pTab */
int iCont, iBreak; /* Beginning and end of the loop over srcTab */
sqlite *db; /* The main database structure */
int keyColumn = -1; /* Column that is the INTEGER PRIMARY KEY */
int endOfLoop; /* Label for the end of the insertion loop */
int useTempTable; /* Store SELECT results in intermediate table */
int srcTab; /* Data comes from this temporary cursor if >=0 */
int iSelectLoop; /* Address of code that implements the SELECT */
int iCleanup; /* Address of the cleanup code */
int iInsertBlock; /* Address of the subroutine used to insert data */
int iCntMem; /* Memory cell used for the row counter */
int isView; /* True if attempting to insert into a view */
int row_triggers_exist = 0; /* True if there are FOR EACH ROW triggers */
int before_triggers; /* True if there are BEFORE triggers */
int after_triggers; /* True if there are AFTER triggers */
int newIdx = -1; /* Cursor for the NEW table */
if( pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
db = pParse->db;
/* Locate the table into which we will be inserting new information.
*/
assert( pTabList->nSrc==1 );
zTab = pTabList->a[0].zName;
if( zTab==0 ) goto insert_cleanup;
pTab = sqliteSrcListLookup(pParse, pTabList);
if( pTab==0 ){
goto insert_cleanup;
}
assert( pTab->iDb<db->nDb );
zDb = db->aDb[pTab->iDb].zName;
if( sqliteAuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
goto insert_cleanup;
}
/* Ensure that:
* (a) the table is not read-only,
* (b) that if it is a view then ON INSERT triggers exist
*/
before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
TK_BEFORE, TK_ROW, 0);
after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
TK_AFTER, TK_ROW, 0);
row_triggers_exist = before_triggers || after_triggers;
isView = pTab->pSelect!=0;
if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
goto insert_cleanup;
}
if( pTab==0 ) goto insert_cleanup;
/* If pTab is really a view, make sure it has been initialized.
*/
if( isView && sqliteViewGetColumnNames(pParse, pTab) ){
goto insert_cleanup;
}
/* Allocate a VDBE
*/
v = sqliteGetVdbe(pParse);
if( v==0 ) goto insert_cleanup;
sqliteBeginWriteOperation(pParse, pSelect || row_triggers_exist, pTab->iDb);
/* if there are row triggers, allocate a temp table for new.* references. */
if( row_triggers_exist ){
newIdx = pParse->nTab++;
}
/* Figure out how many columns of data are supplied. If the data
** is coming from a SELECT statement, then this step also generates
** all the code to implement the SELECT statement and invoke a subroutine
** to process each row of the result. (Template 2.) If the SELECT
** statement uses the the table that is being inserted into, then the
** subroutine is also coded here. That subroutine stores the SELECT
** results in a temporary table. (Template 3.)
*/
if( pSelect ){
/* Data is coming from a SELECT. Generate code to implement that SELECT
*/
int rc, iInitCode;
iInitCode = sqliteVdbeAddOp(v, OP_Goto, 0, 0);
iSelectLoop = sqliteVdbeCurrentAddr(v);
iInsertBlock = sqliteVdbeMakeLabel(v);
rc = sqliteSelect(pParse, pSelect, SRT_Subroutine, iInsertBlock, 0,0,0);
if( rc || pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
iCleanup = sqliteVdbeMakeLabel(v);
sqliteVdbeAddOp(v, OP_Goto, 0, iCleanup);
assert( pSelect->pEList );
nColumn = pSelect->pEList->nExpr;
/* Set useTempTable to TRUE if the result of the SELECT statement
** should be written into a temporary table. Set to FALSE if each
** row of the SELECT can be written directly into the result table.
**
** A temp table must be used if the table being updated is also one
** of the tables being read by the SELECT statement. Also use a
** temp table in the case of row triggers.
*/
if( row_triggers_exist ){
useTempTable = 1;
}else{
int addr = sqliteVdbeFindOp(v, OP_OpenRead, pTab->tnum);
useTempTable = 0;
if( addr>0 ){
VdbeOp *pOp = sqliteVdbeGetOp(v, addr-2);
if( pOp->opcode==OP_Integer && pOp->p1==pTab->iDb ){
useTempTable = 1;
}
}
}
if( useTempTable ){
/* Generate the subroutine that SELECT calls to process each row of
** the result. Store the result in a temporary table
*/
srcTab = pParse->nTab++;
sqliteVdbeResolveLabel(v, iInsertBlock);
sqliteVdbeAddOp(v, OP_MakeRecord, nColumn, 0);
sqliteVdbeAddOp(v, OP_NewRecno, srcTab, 0);
sqliteVdbeAddOp(v, OP_Pull, 1, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, srcTab, 0);
sqliteVdbeAddOp(v, OP_Return, 0, 0);
/* The following code runs first because the GOTO at the very top
** of the program jumps to it. Create the temporary table, then jump
** back up and execute the SELECT code above.
*/
sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
sqliteVdbeAddOp(v, OP_OpenTemp, srcTab, 0);
sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
sqliteVdbeResolveLabel(v, iCleanup);
}else{
sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
}
}else{
/* This is the case if the data for the INSERT is coming from a VALUES
** clause
*/
SrcList dummy;
assert( pList!=0 );
srcTab = -1;
useTempTable = 0;
assert( pList );
nColumn = pList->nExpr;
dummy.nSrc = 0;
for(i=0; i<nColumn; i++){
if( sqliteExprResolveIds(pParse, &dummy, 0, pList->a[i].pExpr) ){
goto insert_cleanup;
}
if( sqliteExprCheck(pParse, pList->a[i].pExpr, 0, 0) ){
goto insert_cleanup;
}
}
}
/* Make sure the number of columns in the source data matches the number
** of columns to be inserted into the table.
*/
if( pColumn==0 && nColumn!=pTab->nCol ){
sqliteErrorMsg(pParse,
"table %S has %d columns but %d values were supplied",
pTabList, 0, pTab->nCol, nColumn);
goto insert_cleanup;
}
if( pColumn!=0 && nColumn!=pColumn->nId ){
sqliteErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
goto insert_cleanup;
}
/* If the INSERT statement included an IDLIST term, then make sure
** all elements of the IDLIST really are columns of the table and
** remember the column indices.
**
** If the table has an INTEGER PRIMARY KEY column and that column
** is named in the IDLIST, then record in the keyColumn variable
** the index into IDLIST of the primary key column. keyColumn is
** the index of the primary key as it appears in IDLIST, not as
** is appears in the original table. (The index of the primary
** key in the original table is pTab->iPKey.)
*/
if( pColumn ){
for(i=0; i<pColumn->nId; i++){
pColumn->a[i].idx = -1;
}
for(i=0; i<pColumn->nId; i++){
for(j=0; j<pTab->nCol; j++){
if( sqliteStrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
pColumn->a[i].idx = j;
if( j==pTab->iPKey ){
keyColumn = i;
}
break;
}
}
if( j>=pTab->nCol ){
if( sqliteIsRowid(pColumn->a[i].zName) ){
keyColumn = i;
}else{
sqliteErrorMsg(pParse, "table %S has no column named %s",
pTabList, 0, pColumn->a[i].zName);
pParse->nErr++;
goto insert_cleanup;
}
}
}
}
/* If there is no IDLIST term but the table has an integer primary
** key, the set the keyColumn variable to the primary key column index
** in the original table definition.
*/
if( pColumn==0 ){
keyColumn = pTab->iPKey;
}
/* Open the temp table for FOR EACH ROW triggers
*/
if( row_triggers_exist ){
sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
}
/* Initialize the count of rows to be inserted
*/
if( db->flags & SQLITE_CountRows ){
iCntMem = pParse->nMem++;
sqliteVdbeAddOp(v, OP_Integer, 0, 0);
sqliteVdbeAddOp(v, OP_MemStore, iCntMem, 1);
}
/* Open tables and indices if there are no row triggers */
if( !row_triggers_exist ){
base = pParse->nTab;
idx = sqliteOpenTableAndIndices(pParse, pTab, base);
pParse->nTab += idx;
}
/* If the data source is a temporary table, then we have to create
** a loop because there might be multiple rows of data. If the data
** source is a subroutine call from the SELECT statement, then we need
** to launch the SELECT statement processing.
*/
if( useTempTable ){
iBreak = sqliteVdbeMakeLabel(v);
sqliteVdbeAddOp(v, OP_Rewind, srcTab, iBreak);
iCont = sqliteVdbeCurrentAddr(v);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
sqliteVdbeResolveLabel(v, iInsertBlock);
}
/* Run the BEFORE and INSTEAD OF triggers, if there are any
*/
endOfLoop = sqliteVdbeMakeLabel(v);
if( before_triggers ){
/* build the NEW.* reference row. Note that if there is an INTEGER
** PRIMARY KEY into which a NULL is being inserted, that NULL will be
** translated into a unique ID for the row. But on a BEFORE trigger,
** we do not know what the unique ID will be (because the insert has
** not happened yet) so we substitute a rowid of -1
*/
if( keyColumn<0 ){
sqliteVdbeAddOp(v, OP_Integer, -1, 0);
}else if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
}else{
sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
sqliteVdbeAddOp(v, OP_Integer, -1, 0);
sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
}
/* Create the new column data
*/
for(i=0; i<pTab->nCol; i++){
if( pColumn==0 ){
j = i;
}else{
for(j=0; j<pColumn->nId; j++){
if( pColumn->a[j].idx==i ) break;
}
}
if( pColumn && j>=pColumn->nId ){
sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
}else if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, j);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, nColumn-j-1, 1);
}else{
sqliteExprCode(pParse, pList->a[j].pExpr);
}
}
sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
/* Fire BEFORE or INSTEAD OF triggers */
if( sqliteCodeRowTrigger(pParse, TK_INSERT, 0, TK_BEFORE, pTab,
newIdx, -1, onError, endOfLoop) ){
goto insert_cleanup;
}
}
/* If any triggers exists, the opening of tables and indices is deferred
** until now.
*/
if( row_triggers_exist && !isView ){
base = pParse->nTab;
idx = sqliteOpenTableAndIndices(pParse, pTab, base);
pParse->nTab += idx;
}
/* Push the record number for the new entry onto the stack. The
** record number is a randomly generate integer created by NewRecno
** except when the table has an INTEGER PRIMARY KEY column, in which
** case the record number is the same as that column.
*/
if( !isView ){
if( keyColumn>=0 ){
if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
}else{
sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
}
/* If the PRIMARY KEY expression is NULL, then use OP_NewRecno
** to generate a unique primary key value.
*/
sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
}else{
sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
}
/* Push onto the stack, data for all columns of the new entry, beginning
** with the first column.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
/* The value of the INTEGER PRIMARY KEY column is always a NULL.
** Whenever this column is read, the record number will be substituted
** in its place. So will fill this column with a NULL to avoid
** taking up data space with information that will never be used. */
sqliteVdbeAddOp(v, OP_String, 0, 0);
continue;
}
if( pColumn==0 ){
j = i;
}else{
for(j=0; j<pColumn->nId; j++){
if( pColumn->a[j].idx==i ) break;
}
}
if( pColumn && j>=pColumn->nId ){
sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
}else if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, j);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, i+nColumn-j, 1);
}else{
sqliteExprCode(pParse, pList->a[j].pExpr);
}
}
/* Generate code to check constraints and generate index keys and
** do the insertion.
*/
sqliteGenerateConstraintChecks(pParse, pTab, base, 0, keyColumn>=0,
0, onError, endOfLoop);
sqliteCompleteInsertion(pParse, pTab, base, 0,0,0,
after_triggers ? newIdx : -1);
}
/* Update the count of rows that are inserted
*/
if( (db->flags & SQLITE_CountRows)!=0 ){
sqliteVdbeAddOp(v, OP_MemIncr, iCntMem, 0);
}
if( row_triggers_exist ){
/* Close all tables opened */
if( !isView ){
sqliteVdbeAddOp(v, OP_Close, base, 0);
for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
sqliteVdbeAddOp(v, OP_Close, idx+base, 0);
}
}
/* Code AFTER triggers */
if( sqliteCodeRowTrigger(pParse, TK_INSERT, 0, TK_AFTER, pTab, newIdx, -1,
onError, endOfLoop) ){
goto insert_cleanup;
}
}
/* The bottom of the loop, if the data source is a SELECT statement
*/
sqliteVdbeResolveLabel(v, endOfLoop);
if( useTempTable ){
sqliteVdbeAddOp(v, OP_Next, srcTab, iCont);
sqliteVdbeResolveLabel(v, iBreak);
sqliteVdbeAddOp(v, OP_Close, srcTab, 0);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Pop, nColumn, 0);
sqliteVdbeAddOp(v, OP_Return, 0, 0);
sqliteVdbeResolveLabel(v, iCleanup);
}
if( !row_triggers_exist ){
/* Close all tables opened */
sqliteVdbeAddOp(v, OP_Close, base, 0);
for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
sqliteVdbeAddOp(v, OP_Close, idx+base, 0);
}
}
sqliteVdbeAddOp(v, OP_SetCounts, 0, 0);
sqliteEndWriteOperation(pParse);
/*
** Return the number of rows inserted.
*/
if( db->flags & SQLITE_CountRows ){
sqliteVdbeOp3(v, OP_ColumnName, 0, 1, "rows inserted", P3_STATIC);
sqliteVdbeAddOp(v, OP_MemLoad, iCntMem, 0);
sqliteVdbeAddOp(v, OP_Callback, 1, 0);
}
insert_cleanup:
sqliteSrcListDelete(pTabList);
if( pList ) sqliteExprListDelete(pList);
if( pSelect ) sqliteSelectDelete(pSelect);
sqliteIdListDelete(pColumn);
}
/*
** Generate code to do a constraint check prior to an INSERT or an UPDATE.
**
** When this routine is called, the stack contains (from bottom to top)
** the following values:
**
** 1. The recno of the row to be updated before the update. This
** value is omitted unless we are doing an UPDATE that involves a
** change to the record number.
**
** 2. The recno of the row after the update.
**
** 3. The data in the first column of the entry after the update.
**
** i. Data from middle columns...
**
** N. The data in the last column of the entry after the update.
**
** The old recno shown as entry (1) above is omitted unless both isUpdate
** and recnoChng are 1. isUpdate is true for UPDATEs and false for
** INSERTs and recnoChng is true if the record number is being changed.
**
** The code generated by this routine pushes additional entries onto
** the stack which are the keys for new index entries for the new record.
** The order of index keys is the same as the order of the indices on
** the pTable->pIndex list. A key is only created for index i if
** aIdxUsed!=0 and aIdxUsed[i]!=0.
**
** This routine also generates code to check constraints. NOT NULL,
** CHECK, and UNIQUE constraints are all checked. If a constraint fails,
** then the appropriate action is performed. There are five possible
** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
**
** Constraint type Action What Happens
** --------------- ---------- ----------------------------------------
** any ROLLBACK The current transaction is rolled back and
** sqlite_exec() returns immediately with a
** return code of SQLITE_CONSTRAINT.
**
** any ABORT Back out changes from the current command
** only (do not do a complete rollback) then
** cause sqlite_exec() to return immediately
** with SQLITE_CONSTRAINT.
**
** any FAIL Sqlite_exec() returns immediately with a
** return code of SQLITE_CONSTRAINT. The
** transaction is not rolled back and any
** prior changes are retained.
**
** any IGNORE The record number and data is popped from
** the stack and there is an immediate jump
** to label ignoreDest.
**
** NOT NULL REPLACE The NULL value is replace by the default
** value for that column. If the default value
** is NULL, the action is the same as ABORT.
**
** UNIQUE REPLACE The other row that conflicts with the row
** being inserted is removed.
**
** CHECK REPLACE Illegal. The results in an exception.
**
** Which action to take is determined by the overrideError parameter.
** Or if overrideError==OE_Default, then the pParse->onError parameter
** is used. Or if pParse->onError==OE_Default then the onError value
** for the constraint is used.
**
** The calling routine must open a read/write cursor for pTab with
** cursor number "base". All indices of pTab must also have open
** read/write cursors with cursor number base+i for the i-th cursor.
** Except, if there is no possibility of a REPLACE action then
** cursors do not need to be open for indices where aIdxUsed[i]==0.
**
** If the isUpdate flag is true, it means that the "base" cursor is
** initially pointing to an entry that is being updated. The isUpdate
** flag causes extra code to be generated so that the "base" cursor
** is still pointing at the same entry after the routine returns.
** Without the isUpdate flag, the "base" cursor might be moved.
*/
void sqliteGenerateConstraintChecks(
Parse *pParse, /* The parser context */
Table *pTab, /* the table into which we are inserting */
int base, /* Index of a read/write cursor pointing at pTab */
char *aIdxUsed, /* Which indices are used. NULL means all are used */
int recnoChng, /* True if the record number will change */
int isUpdate, /* True for UPDATE, False for INSERT */
int overrideError, /* Override onError to this if not OE_Default */
int ignoreDest /* Jump to this label on an OE_Ignore resolution */
){
int i;
Vdbe *v;
int nCol;
int onError;
int addr;
int extra;
int iCur;
Index *pIdx;
int seenReplace = 0;
int jumpInst1, jumpInst2;
int contAddr;
int hasTwoRecnos = (isUpdate && recnoChng);
v = sqliteGetVdbe(pParse);
assert( v!=0 );
assert( pTab->pSelect==0 ); /* This table is not a VIEW */
nCol = pTab->nCol;
/* Test all NOT NULL constraints.
*/
for(i=0; i<nCol; i++){
if( i==pTab->iPKey ){
continue;
}
onError = pTab->aCol[i].notNull;
if( onError==OE_None ) continue;
if( overrideError!=OE_Default ){
onError = overrideError;
}else if( pParse->db->onError!=OE_Default ){
onError = pParse->db->onError;
}else if( onError==OE_Default ){
onError = OE_Abort;
}
if( onError==OE_Replace && pTab->aCol[i].zDflt==0 ){
onError = OE_Abort;
}
sqliteVdbeAddOp(v, OP_Dup, nCol-1-i, 1);
addr = sqliteVdbeAddOp(v, OP_NotNull, 1, 0);
switch( onError ){
case OE_Rollback:
case OE_Abort:
case OE_Fail: {
char *zMsg = 0;
sqliteVdbeAddOp(v, OP_Halt, SQLITE_CONSTRAINT, onError);
sqliteSetString(&zMsg, pTab->zName, ".", pTab->aCol[i].zName,
" may not be NULL", (char*)0);
sqliteVdbeChangeP3(v, -1, zMsg, P3_DYNAMIC);
break;
}
case OE_Ignore: {
sqliteVdbeAddOp(v, OP_Pop, nCol+1+hasTwoRecnos, 0);
sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
break;
}
case OE_Replace: {
sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
sqliteVdbeAddOp(v, OP_Push, nCol-i, 0);
break;
}
default: assert(0);
}
sqliteVdbeChangeP2(v, addr, sqliteVdbeCurrentAddr(v));
}
/* Test all CHECK constraints
*/
/**** TBD ****/
/* If we have an INTEGER PRIMARY KEY, make sure the primary key
** of the new record does not previously exist. Except, if this
** is an UPDATE and the primary key is not changing, that is OK.
*/
if( recnoChng ){
onError = pTab->keyConf;
if( overrideError!=OE_Default ){
onError = overrideError;
}else if( pParse->db->onError!=OE_Default ){
onError = pParse->db->onError;
}else if( onError==OE_Default ){
onError = OE_Abort;
}
if( isUpdate ){
sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
jumpInst1 = sqliteVdbeAddOp(v, OP_Eq, 0, 0);
}
sqliteVdbeAddOp(v, OP_Dup, nCol, 1);
jumpInst2 = sqliteVdbeAddOp(v, OP_NotExists, base, 0);
switch( onError ){
default: {
onError = OE_Abort;
/* Fall thru into the next case */
}
case OE_Rollback:
case OE_Abort:
case OE_Fail: {
sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, onError,
"PRIMARY KEY must be unique", P3_STATIC);
break;
}
case OE_Replace: {
sqliteGenerateRowIndexDelete(pParse->db, v, pTab, base, 0);
if( isUpdate ){
sqliteVdbeAddOp(v, OP_Dup, nCol+hasTwoRecnos, 1);
sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
}
seenReplace = 1;
break;
}
case OE_Ignore: {
assert( seenReplace==0 );
sqliteVdbeAddOp(v, OP_Pop, nCol+1+hasTwoRecnos, 0);
sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
break;
}
}
contAddr = sqliteVdbeCurrentAddr(v);
sqliteVdbeChangeP2(v, jumpInst2, contAddr);
if( isUpdate ){
sqliteVdbeChangeP2(v, jumpInst1, contAddr);
sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
}
}
/* Test all UNIQUE constraints by creating entries for each UNIQUE
** index and making sure that duplicate entries do not already exist.
** Add the new records to the indices as we go.
*/
extra = -1;
for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
if( aIdxUsed && aIdxUsed[iCur]==0 ) continue; /* Skip unused indices */
extra++;
/* Create a key for accessing the index entry */
sqliteVdbeAddOp(v, OP_Dup, nCol+extra, 1);
for(i=0; i<pIdx->nColumn; i++){
int idx = pIdx->aiColumn[i];
if( idx==pTab->iPKey ){
sqliteVdbeAddOp(v, OP_Dup, i+extra+nCol+1, 1);
}else{
sqliteVdbeAddOp(v, OP_Dup, i+extra+nCol-idx, 1);
}
}
jumpInst1 = sqliteVdbeAddOp(v, OP_MakeIdxKey, pIdx->nColumn, 0);
if( pParse->db->file_format>=4 ) sqliteAddIdxKeyType(v, pIdx);
/* Find out what action to take in case there is an indexing conflict */
onError = pIdx->onError;
if( onError==OE_None ) continue; /* pIdx is not a UNIQUE index */
if( overrideError!=OE_Default ){
onError = overrideError;
}else if( pParse->db->onError!=OE_Default ){
onError = pParse->db->onError;
}else if( onError==OE_Default ){
onError = OE_Abort;
}
if( seenReplace ){
if( onError==OE_Ignore ) onError = OE_Replace;
else if( onError==OE_Fail ) onError = OE_Abort;
}
/* Check to see if the new index entry will be unique */
sqliteVdbeAddOp(v, OP_Dup, extra+nCol+1+hasTwoRecnos, 1);
jumpInst2 = sqliteVdbeAddOp(v, OP_IsUnique, base+iCur+1, 0);
/* Generate code that executes if the new index entry is not unique */
switch( onError ){
case OE_Rollback:
case OE_Abort:
case OE_Fail: {
int j, n1, n2;
char zErrMsg[200];
strcpy(zErrMsg, pIdx->nColumn>1 ? "columns " : "column ");
n1 = strlen(zErrMsg);
for(j=0; j<pIdx->nColumn && n1<sizeof(zErrMsg)-30; j++){
char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;
n2 = strlen(zCol);
if( j>0 ){
strcpy(&zErrMsg[n1], ", ");
n1 += 2;
}
if( n1+n2>sizeof(zErrMsg)-30 ){
strcpy(&zErrMsg[n1], "...");
n1 += 3;
break;
}else{
strcpy(&zErrMsg[n1], zCol);
n1 += n2;
}
}
strcpy(&zErrMsg[n1],
pIdx->nColumn>1 ? " are not unique" : " is not unique");
sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, onError, zErrMsg, 0);
break;
}
case OE_Ignore: {
assert( seenReplace==0 );
sqliteVdbeAddOp(v, OP_Pop, nCol+extra+3+hasTwoRecnos, 0);
sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
break;
}
case OE_Replace: {
sqliteGenerateRowDelete(pParse->db, v, pTab, base, 0);
if( isUpdate ){
sqliteVdbeAddOp(v, OP_Dup, nCol+extra+1+hasTwoRecnos, 1);
sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
}
seenReplace = 1;
break;
}
default: assert(0);
}
contAddr = sqliteVdbeCurrentAddr(v);
#if NULL_DISTINCT_FOR_UNIQUE
sqliteVdbeChangeP2(v, jumpInst1, contAddr);
#endif
sqliteVdbeChangeP2(v, jumpInst2, contAddr);
}
}
/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqliteGenerateConstraintChecks.
** The stack must contain keys for all active indices followed by data
** and the recno for the new entry. This routine creates the new
** entries in all indices and in the main table.
**
** The arguments to this routine should be the same as the first six
** arguments to sqliteGenerateConstraintChecks.
*/
void sqliteCompleteInsertion(
Parse *pParse, /* The parser context */
Table *pTab, /* the table into which we are inserting */
int base, /* Index of a read/write cursor pointing at pTab */
char *aIdxUsed, /* Which indices are used. NULL means all are used */
int recnoChng, /* True if the record number will change */
int isUpdate, /* True for UPDATE, False for INSERT */
int newIdx /* Index of NEW table for triggers. -1 if none */
){
int i;
Vdbe *v;
int nIdx;
Index *pIdx;
v = sqliteGetVdbe(pParse);
assert( v!=0 );
assert( pTab->pSelect==0 ); /* This table is not a VIEW */
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
for(i=nIdx-1; i>=0; i--){
if( aIdxUsed && aIdxUsed[i]==0 ) continue;
sqliteVdbeAddOp(v, OP_IdxPut, base+i+1, 0);
}
sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
if( newIdx>=0 ){
sqliteVdbeAddOp(v, OP_Dup, 1, 0);
sqliteVdbeAddOp(v, OP_Dup, 1, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
}
sqliteVdbeAddOp(v, OP_PutIntKey, base,
(pParse->trigStack?0:OPFLAG_NCHANGE) |
(isUpdate?0:OPFLAG_LASTROWID) | OPFLAG_CSCHANGE);
if( isUpdate && recnoChng ){
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
}
}
/*
** Generate code that will open write cursors for a table and for all
** indices of that table. The "base" parameter is the cursor number used
** for the table. Indices are opened on subsequent cursors.
**
** Return the total number of cursors opened. This is always at least
** 1 (for the main table) plus more for each cursor.
*/
int sqliteOpenTableAndIndices(Parse *pParse, Table *pTab, int base){
int i;
Index *pIdx;
Vdbe *v = sqliteGetVdbe(pParse);
assert( v!=0 );
sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
sqliteVdbeOp3(v, OP_OpenWrite, base, pTab->tnum, pTab->zName, P3_STATIC);
for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
sqliteVdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
sqliteVdbeOp3(v, OP_OpenWrite, i+base, pIdx->tnum, pIdx->zName, P3_STATIC);
}
return i;
}
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