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use strict;
use DBI;
use lib 'lib';
use lib '../lib';
$| = 1;
require GenTest::Simplifier::SQL;
#
# This script demonstrates the simplification of queries that fail sporadically. In order to account for the sporadicity,
# we define an oracle() that runs every query 5000 times, and reports that the problem is gone only if all 5000 instances
# returned the same number of rows. Otherwise, it reports that the problem remains, and the Simplifier will use this information
# to further quide the simplification process. More information is available at:
#
# http://forge.mysql.com/wiki/RandomQueryGeneratorSimplification
#
my $query = " SELECT table3 .`date_key` field1 FROM B table1 LEFT JOIN B JOIN ( B table3 JOIN ( AA table4 JOIN ( C table6 JOIN A table7 ON table6 .`varchar_nokey` ) ON table6 .`int_key` ) ON table6 .`int_nokey` ) ON table6 .`varchar_nokey` ON table6 .`date_key` WHERE NOT ( ( NOT ( NOT ( NOT ( NOT table7 .`int_key` >= table1 .`varchar_key` OR table3 .`time_nokey` <> table1 .`pk` ) AND table4 .`date_key` >= table1 .`date_key` ) OR table3 .`time_key` > '2005-07-24 11:06:03' ) AND table1 .`datetime_key` <= 8 ) AND table7 .`pk` < 6 ) GROUP BY field1 ORDER BY field1 , field1 , field1 , field1 LIMIT 7 ";
my $trials = 1000;
my $dsn = 'dbi:mysql:host=127.0.0.1:port=19306:user=root:database=test';
my $dbh = DBI->connect($dsn);
my $simplifier = GenTest::Simplifier::SQL->new(
oracle => sub {
my $query = shift;
print "testing $query\n";
my %outcomes;
foreach my $trial (1..$trials) {
my $sth = $dbh->prepare($query);
$sth->execute();
return 0 if $sth->err() > 0;
$outcomes{$sth->rows()}++;
print "*";
return 1 if scalar(keys %outcomes) > 1;
}
return 0;
}
);
my $simplified = $simplifier->simplify($query);
print "Simplified query:\n$simplified;\n";
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