# 2007 Dec 12

#

# 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 test cases for stressing database

# changes that involve side effects that delete rows from

# the table being changed.  Ticket #2832 shows that in

# older versions of SQLite that behavior was implemented

# incorrectly and resulted in corrupt database files.

#

# $Id: sidedelete.test,v 1.2 2008/08/04 03:51:24 danielk1977 Exp $

#

set testdir [file dirname $argv0]

source $testdir/tester.tcl

# The sequence table is created to store a sequence of integers

# starting with 1.  This is used to reinitialize other tables

# as part of other tests.

#

do_test sidedelete-1.1 {

  execsql {

    CREATE TABLE sequence(a INTEGER PRIMARY KEY);

    INSERT INTO sequence VALUES(1);

    INSERT INTO sequence VALUES(2);

  }

  for {set i 0} {$i<8} {incr i} {

    execsql {

      INSERT INTO sequence SELECT a+(SELECT max(a) FROM sequence) FROM sequence;

    }

  }

  execsql {SELECT count(*) FROM sequence}

} {512}

# Make a series of changes using an UPDATE OR REPLACE and a

# correlated subquery.  This would cause database corruption

# prior to the fix for ticket #2832.

#

do_test sidedelete-2.0 {

  execsql {

    CREATE TABLE t1(a PRIMARY KEY, b);

    CREATE TABLE chng(a PRIMARY KEY, b);

    SELECT count(*) FROM t1;

    SELECT count(*) FROM chng;

  }

} {0 0}

for {set i 2} {$i<=100} {incr i} {

  set n [expr {($i+2)/2}]

  do_test sidedelete-2.$i.1 {

    execsql {

      DELETE FROM t1;

      INSERT INTO t1 SELECT a, a FROM sequence WHERE a<=$i;

      DELETE FROM chng;

      INSERT INTO chng SELECT a*2, a*2+1 FROM sequence WHERE a<=$i/2;

      UPDATE OR REPLACE t1 SET a=(SELECT b FROM chng WHERE a=t1.a);

      SELECT count(*), sum(a) FROM t1;

    }

  } [list $n [expr {$n*$n-1}]]

  integrity_check sidedelete-2.$i.2

}

# This will cause stacks leaks but not database corruption prior

# to the #2832 fix.

#

do_test sidedelete-3.0 {

  execsql {

     DROP TABLE t1;

     CREATE TABLE t1(a PRIMARY KEY);

     SELECT * FROM t1;

  }

} {}

for {set i 1} {$i<=100} {incr i} {

  set n [expr {($i+1)/2}]

  do_test sidedelete-3.$i.1 {

    execsql {

      DELETE FROM t1;

      INSERT INTO t1 SELECT a FROM sequence WHERE a<=$i;

      UPDATE OR REPLACE t1 SET a=a+1;

      SELECT count(*), sum(a) FROM t1;

    }

  } [list $n [expr {$n*($n+1)}]]

  integrity_check sidedelete-3.$i.2

}

finish_test