SQLite

// The text that is parsed as "phrase" is a string starting at A
// and containing (int)(Z-A) characters.  There might be some extra
// whitespace on either end of the text, but that can be removed in
// post-processing, if needed.
//
%type scanpt {const char*}
scanpt(A) ::= . {
  assert( yyLookahead!=YYNOCODE );
  A = yyLookaheadToken.z;



}

// "carglist" is a list of additional constraints that come after the
// column name and column type in a CREATE TABLE statement.
//
carglist ::= carglist ccons.
carglist ::= .

%type trigger_cmd {TriggerStep*}
%destructor trigger_cmd {sqlite3DeleteTriggerStep(pParse->db, $$);}
// UPDATE 
trigger_cmd(A) ::=
   UPDATE(B) orconf(R) trnm(X) tridxby SET setlist(Y) where_opt(Z) scanpt(E).  
   {A = sqlite3TriggerUpdateStep(pParse->db, &X, Y, Z, R, B.z, E);}

// INSERT
trigger_cmd(A) ::= scanpt(B) insert_cmd(R) INTO
                      trnm(X) idlist_opt(F) select(S) scanpt(Z).
   {A = sqlite3TriggerInsertStep(pParse->db,&X,F,S,R,B,Z);/*A-overwrites-R*/}

// DELETE
trigger_cmd(A) ::= DELETE(B) FROM trnm(X) tridxby where_opt(Y) scanpt(E).
   {A = sqlite3TriggerDeleteStep(pParse->db, &X, Y, B.z, E);}

// SELECT
trigger_cmd(A) ::= scanpt(B) select(X) scanpt(E).
   {A = sqlite3TriggerSelectStep(pParse->db, X, B, E); /*A-overwrites-X*/}

// The special RAISE expression that may occur in trigger programs
expr(A) ::= RAISE LP IGNORE RP.  {
  A = sqlite3PExpr(pParse, TK_RAISE, 0, 0); 
  if( A ){
    A->affinity = OE_Ignore;
  }

  u8 orconf;           /* OE_Rollback etc. */
  Trigger *pTrig;      /* The trigger that this step is a part of */
  Select *pSelect;     /* SELECT statement or RHS of INSERT INTO SELECT ... */
  char *zTarget;       /* Target table for DELETE, UPDATE, INSERT */
  Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
  ExprList *pExprList; /* SET clause for UPDATE. */
  IdList *pIdList;     /* Column names for INSERT */
  char *zSpan;         /* Original SQL text of this command */
  TriggerStep *pNext;  /* Next in the link-list */
  TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
};

/*
** The following structure contains information used by the sqliteFix...
** routines as they walk the parse tree to make database references

  Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
  Trigger *sqlite3TriggerList(Parse *, Table *);
  void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
                            int, int, int);
  void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
  void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
  void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
  TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*,
                                        const char*,const char*);
  TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
                                        Select*,u8,const char*,const char*);
  TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8,
                                        const char*,const char*);
  TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*,
                                        const char*,const char*);
  void sqlite3DeleteTrigger(sqlite3*, Trigger*);
  void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
  u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
# define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
# define sqlite3IsToplevel(p) ((p)->pToplevel==0)
#else
# define sqlite3TriggersExist(B,C,D,E,F) 0

    TriggerStep * pTmp = pTriggerStep;
    pTriggerStep = pTriggerStep->pNext;

    sqlite3ExprDelete(db, pTmp->pWhere);
    sqlite3ExprListDelete(db, pTmp->pExprList);
    sqlite3SelectDelete(db, pTmp->pSelect);
    sqlite3IdListDelete(db, pTmp->pIdList);
    sqlite3DbFree(db, pTmp->zSpan);

    sqlite3DbFree(db, pTmp);
  }
}

/*
** Given table pTab, return a list of all the triggers attached to 

triggerfinish_cleanup:
  sqlite3DeleteTrigger(db, pTrig);
  assert( !pParse->pNewTrigger );
  sqlite3DeleteTriggerStep(db, pStepList);
}

/*
** Duplicate a range of text from an SQL statement, then convert all
** whitespace characters into ordinary space characters.
*/
static char *triggerSpanDup(sqlite3 *db, const char *zStart, const char *zEnd){
  char *z = sqlite3DbSpanDup(db, zStart, zEnd);
  int i;
  if( z ) for(i=0; z[i]; i++) if( sqlite3Isspace(z[i]) ) z[i] = ' ';
  return z;
}    

/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step.  Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.  
*/
TriggerStep *sqlite3TriggerSelectStep(
  sqlite3 *db,                /* Database connection */
  Select *pSelect,            /* The SELECT statement */
  const char *zStart,         /* Start of SQL text */
  const char *zEnd            /* End of SQL text */
){
  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep==0 ) {
    sqlite3SelectDelete(db, pSelect);
    return 0;
  }
  pTriggerStep->op = TK_SELECT;
  pTriggerStep->pSelect = pSelect;
  pTriggerStep->orconf = OE_Default;
  pTriggerStep->zSpan = triggerSpanDup(db, zStart, zEnd);
  return pTriggerStep;
}

/*
** Allocate space to hold a new trigger step.  The allocated space
** holds both the TriggerStep object and the TriggerStep.target.z string.
**
** If an OOM error occurs, NULL is returned and db->mallocFailed is set.
*/
static TriggerStep *triggerStepAllocate(
  sqlite3 *db,                /* Database connection */
  u8 op,                      /* Trigger opcode */
  Token *pName,               /* The target name */
  const char *zStart,         /* Start of SQL text */
  const char *zEnd            /* End of SQL text */
){
  TriggerStep *pTriggerStep;

  pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep) + pName->n + 1);
  if( pTriggerStep ){
    char *z = (char*)&pTriggerStep[1];
    memcpy(z, pName->z, pName->n);
    sqlite3Dequote(z);
    pTriggerStep->zTarget = z;
    pTriggerStep->op = op;
    pTriggerStep->zSpan = triggerSpanDup(db, zStart, zEnd);
  }
  return pTriggerStep;
}

/*
** Build a trigger step out of an INSERT statement.  Return a pointer
** to the new trigger step.
**
** The parser calls this routine when it sees an INSERT inside the
** body of a trigger.
*/
TriggerStep *sqlite3TriggerInsertStep(
  sqlite3 *db,        /* The database connection */
  Token *pTableName,  /* Name of the table into which we insert */
  IdList *pColumn,    /* List of columns in pTableName to insert into */
  Select *pSelect,    /* A SELECT statement that supplies values */
  u8 orconf,          /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
  const char *zStart, /* Start of SQL text */
  const char *zEnd    /* End of SQL text */
){
  TriggerStep *pTriggerStep;

  assert(pSelect != 0 || db->mallocFailed);

  pTriggerStep = triggerStepAllocate(db, TK_INSERT, pTableName, zStart, zEnd);
  if( pTriggerStep ){
    pTriggerStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
    pTriggerStep->pIdList = pColumn;
    pTriggerStep->orconf = orconf;
  }else{
    sqlite3IdListDelete(db, pColumn);
  }

** sees an UPDATE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerUpdateStep(
  sqlite3 *db,         /* The database connection */
  Token *pTableName,   /* Name of the table to be updated */
  ExprList *pEList,    /* The SET clause: list of column and new values */
  Expr *pWhere,        /* The WHERE clause */
  u8 orconf,           /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
  const char *zStart,  /* Start of SQL text */
  const char *zEnd     /* End of SQL text */
){
  TriggerStep *pTriggerStep;

  pTriggerStep = triggerStepAllocate(db, TK_UPDATE, pTableName, zStart, zEnd);
  if( pTriggerStep ){
    pTriggerStep->pExprList = sqlite3ExprListDup(db, pEList, EXPRDUP_REDUCE);
    pTriggerStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
    pTriggerStep->orconf = orconf;
  }
  sqlite3ExprListDelete(db, pEList);
  sqlite3ExprDelete(db, pWhere);
  return pTriggerStep;
}

/*
** Construct a trigger step that implements a DELETE statement and return
** a pointer to that trigger step.  The parser calls this routine when it
** sees a DELETE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerDeleteStep(
  sqlite3 *db,            /* Database connection */
  Token *pTableName,      /* The table from which rows are deleted */
  Expr *pWhere,           /* The WHERE clause */
  const char *zStart,     /* Start of SQL text */
  const char *zEnd        /* End of SQL text */
){
  TriggerStep *pTriggerStep;

  pTriggerStep = triggerStepAllocate(db, TK_DELETE, pTableName, zStart, zEnd);
  if( pTriggerStep ){
    pTriggerStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
    pTriggerStep->orconf = OE_Default;
  }
  sqlite3ExprDelete(db, pWhere);
  return pTriggerStep;
}

    **   END;
    **
    **   INSERT INTO t1 ... ;            -- insert into t2 uses REPLACE policy
    **   INSERT OR IGNORE INTO t1 ... ;  -- insert into t2 uses IGNORE policy
    */
    pParse->eOrconf = (orconf==OE_Default)?pStep->orconf:(u8)orconf;
    assert( pParse->okConstFactor==0 );

#ifndef SQLITE_OMIT_TRACE
    sqlite3VdbeAddOp4(v, OP_Trace, 0x7fffffff, 1, 0,
                      sqlite3MPrintf(db, "-- %s", pStep->zSpan),
                      P4_DYNAMIC);
#endif

    switch( pStep->op ){
      case TK_UPDATE: {
        sqlite3Update(pParse, 
          targetSrcList(pParse, pStep),
          sqlite3ExprListDup(db, pStep->pExprList, 0), 
          sqlite3ExprDup(db, pStep->pWhere, 0), 

  }

  REGISTER_TRACE(pOp->p3, pOut);
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Trace P1 P2 * P4 *
**
** Write P4 on the statement trace output if statement tracing is
** enabled.
**
** Operand P1 must be 0x7fffffff and P2 must positive.
*/
/* Opcode: Init P1 P2 P3 P4 *
** Synopsis: Start at P2
**
** Programs contain a single instance of this opcode as the very first
** opcode.
**
** If tracing is enabled (by the sqlite3_trace()) interface, then
** the UTF-8 string contained in P4 is emitted on the trace callback.
** Or if P4 is blank, use the string returned by sqlite3_sql().
**
** If P2 is not zero, jump to instruction P2.
**
** Increment the value of P1 so that OP_Once opcodes will jump the
** first time they are evaluated for this run.
**
** If P3 is not zero, then it is an address to jump to if an SQLITE_CORRUPT
** error is encountered.
*/
case OP_Trace:
case OP_Init: {          /* jump */
  char *zTrace;
  int i;

  /* If the P4 argument is not NULL, then it must be an SQL comment string.
  ** The "--" string is broken up to prevent false-positives with srcck1.c.
  **
  ** This assert() provides evidence for:
  ** EVIDENCE-OF: R-50676-09860 The callback can compute the same text that
  ** would have been returned by the legacy sqlite3_trace() interface by
  ** using the X argument when X begins with "--" and invoking
  ** sqlite3_expanded_sql(P) otherwise.
  */
  assert( pOp->p4.z==0 || strncmp(pOp->p4.z, "-" "- ", 3)==0 );

  /* OP_Init is always instruction 0 */
  assert( pOp==p->aOp || pOp->opcode==OP_Trace );

#ifndef SQLITE_OMIT_TRACE
  if( (db->mTrace & (SQLITE_TRACE_STMT|SQLITE_TRACE_LEGACY))!=0
   && !p->doingRerun
   && (zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0
  ){
#ifndef SQLITE_OMIT_DEPRECATED

  ){
    sqlite3DebugPrintf("SQL-trace: %s\n", zTrace);
  }
#endif /* SQLITE_DEBUG */
#endif /* SQLITE_OMIT_TRACE */
  assert( pOp->p2>0 );
  if( pOp->p1>=sqlite3GlobalConfig.iOnceResetThreshold ){
    if( pOp->opcode==OP_Trace ) break;
    for(i=1; i<p->nOp; i++){
      if( p->aOp[i].opcode==OP_Once ) p->aOp[i].p1 = 0;
    }
    pOp->p1 = 0;
  }
  pOp->p1++;
  p->aCounter[SQLITE_STMTSTATUS_RUN]++;

    proc trace_proc cmd {
      lappend ::TRACE_OUT [string trim $cmd]
    }
    db eval {
      UPDATE t1 SET a=a+1;
    }
    set TRACE_OUT
  } {{UPDATE t1 SET a=a+1;} {-- TRIGGER r1t1} {-- UPDATE t2 SET a=new.a WHERE rowid=new.rowid} {-- TRIGGER r1t2} {-- SELECT 'hello'} {-- TRIGGER r1t1} {-- UPDATE t2 SET a=new.a WHERE rowid=new.rowid} {-- TRIGGER r1t2} {-- SELECT 'hello'} {-- TRIGGER r1t1} {-- UPDATE t2 SET a=new.a WHERE rowid=new.rowid} {-- TRIGGER r1t2} {-- SELECT 'hello'}}
}

# With 3.6.21, we add the ability to expand host parameters in the trace
# output.  Test this feature.
#
do_test trace-6.1 {
  set ::t6int [expr {3+3}]