SQLite

        if( db->flags&SQLITE_RecTriggers ){
          pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
        }
        if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){
          sqlite3MultiWrite(pParse);
          sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
                                   regNewData, 1, 0, OE_Replace, 1, -1);
          sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRowidOk, regNewData);
          sqlite3RowidConstraint(pParse, OE_Abort, pTab);
        }else{
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
          assert( HasRowid(pTab) );
          /* This OP_Delete opcode fires the pre-update-hook only. It does
          ** not modify the b-tree. It is more efficient to let the coming
          ** OP_Insert replace the existing entry than it is to delete the
          ** existing entry and then insert a new one. */

      case OE_Ignore: {
        testcase( onError==OE_Ignore );
        sqlite3VdbeGoto(v, ignoreDest);
        break;
      }
      default: {
        Trigger *pTrigger = 0;
        int bRetryConstraintCheck = 0;
        assert( onError==OE_Replace );
        if( db->flags&SQLITE_RecTriggers ){
          pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
        }
        if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){
          sqlite3MultiWrite(pParse);
          bRetryConstraintCheck = 1;
        }
        sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
            regR, nPkField, 0, OE_Replace,
            (pIdx==pPk ? ONEPASS_SINGLE : ONEPASS_OFF), iThisCur);
        if( bRetryConstraintCheck ){
          sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur, addrUniqueOk,
                               regIdx, pIdx->nKeyCol); VdbeCoverage(v);
          sqlite3UniqueConstraint(pParse, OE_Abort, pIdx);
        }
        seenReplace = 1;
        break;
      }
    }
    if( pUpIdx==pIdx ){
      sqlite3VdbeGoto(v, upsertJump+1);
      sqlite3VdbeJumpHere(v, upsertBypass);

# 2001-09-15
#
# 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 implements regression tests for SQLite library.  The
# focus of this file is testing the INSERT statement.
#


set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Try to insert into a non-existant table.
#
do_test insert-1.1 {

do_execsql_test insert-14.1 {
  DROP TABLE IF EXISTS t14;
  CREATE TABLE t14(x INTEGER PRIMARY KEY);
  INSERT INTO t14 VALUES(CASE WHEN 1 THEN null END);
  SELECT x FROM t14;
} {1}

integrity_check insert-14.2

# 2019-08-12.
#
do_execsql_test insert-15.1 {
  DROP TABLE IF EXISTS t1;
  DROP TABLE IF EXISTS t2;
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b TEXT);
  CREATE INDEX i1 ON t1(b);
  CREATE TABLE t2(a, b);
  INSERT INTO t2 VALUES(4, randomblob(31000));
  INSERT INTO t2 VALUES(4, randomblob(32000));
  INSERT INTO t2 VALUES(4, randomblob(33000));
  REPLACE INTO t1 SELECT a, b FROM t2;
  SELECT a, length(b) FROM t1;
} {4 33000}

# 2019-10-16
# ticket https://www.sqlite.org/src/info/a8a4847a2d96f5de
# On a REPLACE INTO, if an AFTER trigger adds back the conflicting
# row, you can end up with the wrong number of rows in an index.
#
db close
sqlite3 db :memory:
do_catchsql_test insert-16.1 {
  PRAGMA recursive_triggers = true;
  CREATE TABLE t0(c0,c1);
  CREATE UNIQUE INDEX i0 ON t0(c0);
  INSERT INTO t0(c0,c1) VALUES(123,1);
  CREATE TRIGGER tr0 AFTER DELETE ON t0
  BEGIN
    INSERT INTO t0 VALUES(123,2);
  END;
  REPLACE INTO t0(c0,c1) VALUES(123,3);
} {1 {UNIQUE constraint failed: t0.c0}}
do_execsql_test insert-16.2 {
  SELECT * FROM t0;
} {123 1}
integrity_check insert-16.3
do_catchsql_test insert-16.4 {
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
  CREATE INDEX t1b ON t1(b);
  INSERT INTO t1 VALUES(1, 'one');
  CREATE TRIGGER tr3 AFTER DELETE ON t1 BEGIN
    INSERT INTO t1 VALUES(1, 'three');
  END;
  REPLACE INTO t1 VALUES(1, 'two');
} {1 {UNIQUE constraint failed: t1.a}}
integrity_check insert-16.5
do_catchsql_test insert-16.6 {
  PRAGMA foreign_keys = 1;
  CREATE TABLE p1(a, b UNIQUE);
  CREATE TABLE c1(c, d REFERENCES p1(b) ON DELETE CASCADE);
  CREATE TRIGGER tr6 AFTER DELETE ON c1 BEGIN
    INSERT INTO p1 VALUES(4, 1);
  END;
  INSERT INTO p1 VALUES(1, 1);
  INSERT INTO c1 VALUES(2, 1);
  REPLACE INTO p1 VALUES(3, 1);
} {1 {UNIQUE constraint failed: p1.b}}
integrity_check insert-16.7



  

finish_test