fix(column_info): use show columns to describe

[johnjelinek]

Resolves this error: You have an error in your SQL syntax
Fixes #439

[dveeden]

This looks fine. Could you add a test for this?

DBD-mysql/t/40catalog.t

Lines 258 to 303 in 8d671d1

	#
	# column_info() tests
	#
	SKIP: {
	ok($dbh->do(qq{DROP TABLE IF EXISTS t1}), "cleaning up");
	ok($dbh->do(qq{CREATE TABLE t1 (a INT PRIMARY KEY AUTO_INCREMENT,
	b INT,
	`a_` INT,
	`a'b` INT,
	bar INT
	)}), "creating table");
	#
	# Bug #26603: (one part) add mysql_is_autoincrement
	#
	$sth= $dbh->column_info(undef, undef, "t1", 'a');
	my ($info)= $sth->fetchall_arrayref({});
	is($info->[0]->{mysql_is_auto_increment}, 1);
	$sth= $dbh->column_info(undef, undef, "t1", 'b');
	($info)= $sth->fetchall_arrayref({});
	is($info->[0]->{mysql_is_auto_increment}, 0);
	#
	# Test that wildcards and odd names are handled correctly
	#
	$sth= $dbh->column_info(undef, undef, "t1", "a%");
	($info)= $sth->fetchall_arrayref({});
	is(scalar @$info, 3);
	$sth= $dbh->column_info(undef, undef, "t1", "a" . $dbh->get_info(14) . "_");
	($info)= $sth->fetchall_arrayref({});
	is(scalar @$info, 1);
	$sth= $dbh->column_info(undef, undef, "t1", "a'b");
	($info)= $sth->fetchall_arrayref({});
	is(scalar @$info, 1);
	#
	# The result set is ordered by TABLE_CAT, TABLE_SCHEM, TABLE_NAME and ORDINAL_POSITION.
	#
	$sth= $dbh->column_info(undef, undef, "t1", undef);
	($info)= $sth->fetchall_arrayref({});
	is(join(' ++ ', map { $_->{COLUMN_NAME} } @{$info}), "a ++ b ++ a_ ++ a'b ++ bar");
	ok($dbh->do(qq{DROP TABLE IF EXISTS t1}), "cleaning up");
	$dbh->disconnect();
	};