[dbsrgits/SQL-Translator.git] / lib / SQL / Translator / Producer / SQLite.pm

package SQL::Translator::Producer::SQLite;

# -------------------------------------------------------------------
# $Id: SQLite.pm,v 1.15 2006-08-26 11:35:31 schiffbruechige Exp $
# -------------------------------------------------------------------
# Copyright (C) 2002-4 SQLFairy Authors
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; version 2.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
# 02111-1307  USA
# -------------------------------------------------------------------

=head1 NAME

SQL::Translator::Producer::SQLite - SQLite producer for SQL::Translator

=head1 SYNOPSIS

  use SQL::Translator;

  my $t = SQL::Translator->new( parser => '...', producer => 'SQLite' );
  $t->translate;

=head1 DESCRIPTION

This module will produce text output of the schema suitable for SQLite.

=cut

use strict;
use Data::Dumper;
use SQL::Translator::Schema::Constants;
use SQL::Translator::Utils qw(debug header_comment);

use vars qw[ $VERSION $DEBUG $WARN ];

$VERSION = sprintf "%d.%02d", q$Revision: 1.15 $ =~ /(\d+)\.(\d+)/;
$DEBUG = 0 unless defined $DEBUG;
$WARN = 0 unless defined $WARN;

my %used_identifiers = ();
my $max_id_length    = 30;
my %global_names;
my %truncated;

sub produce {
    my $translator     = shift;
    local $DEBUG       = $translator->debug;
    local $WARN        = $translator->show_warnings;
    my $no_comments    = $translator->no_comments;
    my $add_drop_table = $translator->add_drop_table;
    my $schema         = $translator->schema;

    debug("PKG: Beginning production\n");

    my $create = '';
    $create .= header_comment unless ($no_comments);
    $create .= "BEGIN TRANSACTION;\n\n";

    my @table_defs = ();
    for my $table ( $schema->get_tables ) {
        my @defs = create_table($table, { no_comments => $no_comments,
                                          add_drop_table => $add_drop_table,});
        my $create = shift @defs;
        $create .= ";\n";
        push @table_defs, $create, map( { "$_;" } @defs), "";
    }

#    $create .= "COMMIT;\n";

    return wantarray ? ($create, @table_defs, "COMMIT;\n") : join("\n", ($create, @table_defs, "COMMIT;\n"));
}

# -------------------------------------------------------------------
sub mk_name {
    my ($basename, $type, $scope, $critical) = @_;
    my $basename_orig = $basename;
    my $max_name      = $type 
                        ? $max_id_length - (length($type) + 1) 
                        : $max_id_length;
    $basename         = substr( $basename, 0, $max_name ) 
                        if length( $basename ) > $max_name;
    my $name          = $type ? "${type}_$basename" : $basename;

    if ( $basename ne $basename_orig and $critical ) {
        my $show_type = $type ? "+'$type'" : "";
        warn "Truncating '$basename_orig'$show_type to $max_id_length ",
            "character limit to make '$name'\n" if $WARN;
        $truncated{ $basename_orig } = $name;
    }

    $scope ||= \%global_names;
    if ( my $prev = $scope->{ $name } ) {
        my $name_orig = $name;
        $name        .= sprintf( "%02d", ++$prev );
        substr($name, $max_id_length - 3) = "00" 
            if length( $name ) > $max_id_length;

        warn "The name '$name_orig' has been changed to ",
             "'$name' to make it unique.\n" if $WARN;

        $scope->{ $name_orig }++;
    }

    $scope->{ $name }++;
    return $name;
}

sub create_table
{
    my ($table, $options) = @_;

    my $table_name = $table->name;
    my $no_comments = $options->{no_comments};
    my $add_drop_table = $options->{add_drop_table};

    debug("PKG: Looking at table '$table_name'\n");

    my ( @index_defs, @constraint_defs, @trigger_defs );
    my @fields = $table->get_fields or die "No fields in $table_name";

    my $temp = $options->{temporary_table} ? 'TEMPORARY ' : '';
    #
    # Header.
    #
    my $create = '';
    $create .= "--\n-- Table: $table_name\n--\n" unless $no_comments;
    $create .= qq[DROP TABLE $table_name;\n] if $add_drop_table;
    $create .= "CREATE ${temp}TABLE $table_name (\n";

    #
    # Comments
    #
    if ( $table->comments and !$no_comments ){
        $create .= "-- Comments: \n-- ";
        $create .= join "\n-- ",  $table->comments;
        $create .= "\n--\n\n";
    }

    #
    # How many fields in PK?
    #
    my $pk        = $table->primary_key;
    my @pk_fields = $pk ? $pk->fields : ();

    #
    # Fields
    #
    my ( @field_defs, $pk_set );
    for my $field ( @fields ) {
        push @field_defs, create_field($field);
    }

    if ( 
         scalar @pk_fields > 1 
         || 
         ( @pk_fields && !grep /INTEGER PRIMARY KEY/, @field_defs ) 
         ) {
        push @field_defs, 'PRIMARY KEY (' . join(', ', @pk_fields ) . ')';
    }

    #
    # Indices
    #
    my $idx_name_default = 'A';
    for my $index ( $table->get_indices ) {
        push @index_defs, create_index($index);
    }

    #
    # Constraints
    #
    my $c_name_default = 'A';
    for my $c ( $table->get_constraints ) {
        next unless $c->type eq UNIQUE; 
        push @constraint_defs, create_constraint($c);
    }

    $create .= join(",\n", map { "  $_" } @field_defs ) . "\n)";

    return ($create, @index_defs, @constraint_defs, @trigger_defs );
}

sub create_field
{
    my ($field, $options) = @_;

    my $field_name = $field->name;
    debug("PKG: Looking at field '$field_name'\n");
    my $field_comments = $field->comments 
        ? "-- " . $field->comments . "\n  " 
        : '';

    my $field_def = $field_comments.$field_name;

    # data type and size
    my $size      = $field->size;
    my $data_type = $field->data_type;
    $data_type    = 'varchar' if lc $data_type eq 'set';
    $data_type  = 'blob' if lc $data_type eq 'bytea';

    if ( lc $data_type =~ /(text|blob)/i ) {
        $size = undef;
    }

#             if ( $data_type =~ /timestamp/i ) {
#                 push @trigger_defs, 
#                     "CREATE TRIGGER ts_${table_name} ".
#                     "after insert on $table_name\n".
#                     "begin\n".
#                     "  update $table_name set $field_name=timestamp() ".
#                        "where id=new.id;\n".
#                     "end;\n"
#                 ;
#
#            }

    #
    # SQLite is generally typeless, but newer versions will
    # make a field autoincrement if it is declared as (and
    # *only* as) INTEGER PRIMARY KEY
    #
    my $pk        = $field->table->primary_key;
    my @pk_fields = $pk ? $pk->fields : ();

    if ( 
         $field->is_primary_key && 
         scalar @pk_fields == 1 &&
         (
          $data_type =~ /int(eger)?$/i
          ||
          ( $data_type =~ /^number?$/i && $size !~ /,/ )
          )
         ) {
        $data_type = 'INTEGER PRIMARY KEY';
        $size      = undef;
#        $pk_set    = 1;
    }

    $field_def .= sprintf " %s%s", $data_type, 
    ( !$field->is_auto_increment && $size ) ? "($size)" : '';

    # Null?
    $field_def .= ' NOT NULL' unless $field->is_nullable;

    # Default?  XXX Need better quoting!
    my $default = $field->default_value;
    if ( defined $default ) {
        if ( uc $default eq 'NULL') {
            $field_def .= ' DEFAULT NULL';
        } elsif ( $default eq 'now()' ||
                  $default eq 'CURRENT_TIMESTAMP' ) {
            $field_def .= ' DEFAULT CURRENT_TIMESTAMP';
        } elsif ( $default =~ /val\(/ ) {
            next;
        } else {
            $field_def .= " DEFAULT '$default'";
        }
    }

    return $field_def;

}

sub create_index
{
    my ($index, $options) = @_;

    my $name   = $index->name;
    $name      = mk_name($index->table->name, $name);

    my $type   = $index->type eq 'UNIQUE' ? "UNIQUE " : ''; 

    # strip any field size qualifiers as SQLite doesn't like these
    my @fields = map { s/\(\d+\)$//; $_ } $index->fields;
    my $index_def =  
    "CREATE ${type}INDEX $name ON " . $index->table->name .
        ' (' . join( ', ', @fields ) . ')';

    return $index_def;
}

sub create_constraint
{
    my ($c, $options) = @_;

    my $name   = $c->name;
    $name      = mk_name($c->table->name, $name);
    my @fields = $c->fields;

    my $c_def =  
    "CREATE UNIQUE INDEX $name ON " . $c->table->name .
        ' (' . join( ', ', @fields ) . ')';

    return $c_def;
}

sub alter_table { } # Noop

sub add_field {
  my ($field) = @_;

  return sprintf("ALTER TABLE %s ADD COLUMN %s",
      $field->table->name, create_field($field))
}

sub alter_create_index {
  my ($index) = @_;

  # This might cause name collisions
  return create_index($index);
}

sub alter_create_constraint {
  my ($constraint) = @_;

  return create_constraint($constraint) if $constraint->type eq 'UNIQUE';
}

sub alter_drop_constraint { alter_drop_index(@_) }

sub alter_drop_index {
  my ($constraint) = @_;

  return sprintf("DROP INDEX %s ON %s",
      $constraint->name, $constraint->table->name);
}

sub batch_alter_table {
  my ($table, $diffs) = @_;

  $DB::single = 1 if $table->name eq 'deleted'; 

  # If we have any of the following
  #
  #  rename_field
  #  alter_field
  #  drop_field
  #
  # we need to do the following <http://www.sqlite.org/faq.html#q11>
  #
  # BEGIN TRANSACTION;
  # CREATE TEMPORARY TABLE t1_backup(a,b);
  # INSERT INTO t1_backup SELECT a,b FROM t1;
  # DROP TABLE t1;
  # CREATE TABLE t1(a,b);
  # INSERT INTO t1 SELECT a,b FROM t1_backup;
  # DROP TABLE t1_backup;
  # COMMIT;
  #
  # Fun, eh?

  if ( @{$diffs->{rename_field}} == 0 &&
       @{$diffs->{alter_field}}  == 0 &&
       @{$diffs->{drop_field}}   == 0) {
    return join("\n", map { 
        my $meth = __PACKAGE__->can($_) or die __PACKAGE__ . " cant $_";
        map { my $sql = $meth->(ref $_ eq 'ARRAY' ? @$_ : $_); $sql ?  ("$sql;") : () } @{ $diffs->{$_} }
        
      } grep { @{$diffs->{$_}} } keys %$diffs);
  }


  my @sql;
  
  do {
    local $table->{name} = $table->name . '_temp_alter';
    # We only want the table - dont care about indexes on tmp table
    my ($table_sql) = create_table($table, {no_comments => 1, temporary_table => 1});
    push @sql,$table_sql;
  };

  push @sql, "INSERT INTO @{[$table]}_temp_alter SELECT @{[ join(', ', $table->get_fields)]} FROM @{[$table]}",
             "DROP TABLE @{[$table]}",
             create_table($table, { no_comments => 1 }),
             "INSERT INTO @{[$table]} SELECT @{[ join(', ', $table->get_fields)]} FROM @{[$table]}_temp_alter",
             "DROP TABLE @{[$table]}_temp_alter";

  return join(";\n", @sql, "");
}

sub drop_table {
  my ($table) = @_;
  return "DROP TABLE $table;";
}

1;

=pod

=head1 SEE ALSO

SQL::Translator, http://www.sqlite.org/.

=head1 AUTHOR

Ken Y. Clark C<< <kclark@cpan.orgE> >>.

Diff code added by Ash Berlin C<< <ash@cpan.org> >>.

=cut
Commit	Line	Data
758ab1cd	1	package SQL::Translator::Producer::SQLite;
	2
	3	# -------------------------------------------------------------------
8619aed2	4	# $Id: SQLite.pm,v 1.15 2006-08-26 11:35:31 schiffbruechige Exp $
758ab1cd	5	# -------------------------------------------------------------------
977651a5	6	# Copyright (C) 2002-4 SQLFairy Authors
758ab1cd	7	#
	8	# This program is free software; you can redistribute it and/or
	9	# modify it under the terms of the GNU General Public License as
	10	# published by the Free Software Foundation; version 2.
	11	#
	12	# This program is distributed in the hope that it will be useful, but
	13	# WITHOUT ANY WARRANTY; without even the implied warranty of
	14	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	# General Public License for more details.
	16	#
	17	# You should have received a copy of the GNU General Public License
	18	# along with this program; if not, write to the Free Software
	19	# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	20	# 02111-1307 USA
	21	# -------------------------------------------------------------------
	22
20770e44	23	=head1 NAME
	24
	25	SQL::Translator::Producer::SQLite - SQLite producer for SQL::Translator
	26
	27	=head1 SYNOPSIS
	28
	29	use SQL::Translator;
	30
	31	my $t = SQL::Translator->new( parser => '...', producer => 'SQLite' );
	32	$t->translate;
	33
	34	=head1 DESCRIPTION
	35
	36	This module will produce text output of the schema suitable for SQLite.
	37
	38	=cut
	39
758ab1cd	40	use strict;
758ab1cd	41	use Data::Dumper;
b21bf652	42	use SQL::Translator::Schema::Constants;
5ee19df8	43	use SQL::Translator::Utils qw(debug header_comment);
758ab1cd	44
758ab1cd	45	use vars qw[ $VERSION $DEBUG $WARN ];
5ee19df8	46
8619aed2	47	$VERSION = sprintf "%d.%02d", q$Revision: 1.15 $ =~ /(\d+)\.(\d+)/;
5ee19df8	48	$DEBUG = 0 unless defined $DEBUG;
5ee19df8	49	$WARN = 0 unless defined $WARN;
758ab1cd	50
	51	my %used_identifiers = ();
	52	my $max_id_length = 30;
	53	my %global_names;
	54	my %truncated;
	55
758ab1cd	56	sub produce {
a1d94525	57	my $translator = shift;
	58	local $DEBUG = $translator->debug;
	59	local $WARN = $translator->show_warnings;
	60	my $no_comments = $translator->no_comments;
	61	my $add_drop_table = $translator->add_drop_table;
	62	my $schema = $translator->schema;
758ab1cd	63
1a24938d	64	debug("PKG: Beginning production\n");
758ab1cd	65
a5a882f0	66	my $create = '';
5ee19df8	67	$create .= header_comment unless ($no_comments);
a5a882f0	68	$create .= "BEGIN TRANSACTION;\n\n";
758ab1cd	69
bfb5a568	70	my @table_defs = ();
b21bf652	71	for my $table ( $schema->get_tables ) {
4d438549	72	my @defs = create_table($table, { no_comments => $no_comments,
	73	add_drop_table => $add_drop_table,});
	74	my $create = shift @defs;
	75	$create .= ";\n";
	76	push @table_defs, $create, map( { "$_;" } @defs), "";
a5a882f0	77	}
a5a882f0	78
bfb5a568	79	# $create .= "COMMIT;\n";
a5a882f0	80
bfb5a568	81	return wantarray ? ($create, @table_defs, "COMMIT;\n") : join("\n", ($create, @table_defs, "COMMIT;\n"));
758ab1cd	82	}
758ab1cd	83
758ab1cd	84	# -------------------------------------------------------------------
	85	sub mk_name {
	86	my ($basename, $type, $scope, $critical) = @_;
	87	my $basename_orig = $basename;
	88	my $max_name = $type
	89	? $max_id_length - (length($type) + 1)
	90	: $max_id_length;
	91	$basename = substr( $basename, 0, $max_name )
	92	if length( $basename ) > $max_name;
	93	my $name = $type ? "${type}_$basename" : $basename;
	94
	95	if ( $basename ne $basename_orig and $critical ) {
	96	my $show_type = $type ? "+'$type'" : "";
	97	warn "Truncating '$basename_orig'$show_type to $max_id_length ",
	98	"character limit to make '$name'\n" if $WARN;
	99	$truncated{ $basename_orig } = $name;
	100	}
	101
	102	$scope \|\|= \%global_names;
	103	if ( my $prev = $scope->{ $name } ) {
	104	my $name_orig = $name;
	105	$name .= sprintf( "%02d", ++$prev );
	106	substr($name, $max_id_length - 3) = "00"
	107	if length( $name ) > $max_id_length;
	108
	109	warn "The name '$name_orig' has been changed to ",
	110	"'$name' to make it unique.\n" if $WARN;
	111
	112	$scope->{ $name_orig }++;
	113	}
	114
	115	$scope->{ $name }++;
	116	return $name;
	117	}
	118
bfb5a568	119	sub create_table
	120	{
	121	my ($table, $options) = @_;
758ab1cd	122
bfb5a568	123	my $table_name = $table->name;
	124	my $no_comments = $options->{no_comments};
	125	my $add_drop_table = $options->{add_drop_table};
	126
	127	debug("PKG: Looking at table '$table_name'\n");
	128
	129	my ( @index_defs, @constraint_defs, @trigger_defs );
	130	my @fields = $table->get_fields or die "No fields in $table_name";
	131
4d438549	132	my $temp = $options->{temporary_table} ? 'TEMPORARY ' : '';
bfb5a568	133	#
	134	# Header.
	135	#
	136	my $create = '';
	137	$create .= "--\n-- Table: $table_name\n--\n" unless $no_comments;
	138	$create .= qq[DROP TABLE $table_name;\n] if $add_drop_table;
4d438549	139	$create .= "CREATE ${temp}TABLE $table_name (\n";
bfb5a568	140
	141	#
	142	# Comments
	143	#
	144	if ( $table->comments and !$no_comments ){
	145	$create .= "-- Comments: \n-- ";
	146	$create .= join "\n-- ", $table->comments;
	147	$create .= "\n--\n\n";
	148	}
	149
	150	#
	151	# How many fields in PK?
	152	#
	153	my $pk = $table->primary_key;
	154	my @pk_fields = $pk ? $pk->fields : ();
	155
	156	#
	157	# Fields
	158	#
	159	my ( @field_defs, $pk_set );
	160	for my $field ( @fields ) {
	161	push @field_defs, create_field($field);
	162	}
	163
	164	if (
	165	scalar @pk_fields > 1
	166	\|\|
	167	( @pk_fields && !grep /INTEGER PRIMARY KEY/, @field_defs )
	168	) {
	169	push @field_defs, 'PRIMARY KEY (' . join(', ', @pk_fields ) . ')';
	170	}
	171
	172	#
	173	# Indices
	174	#
	175	my $idx_name_default = 'A';
	176	for my $index ( $table->get_indices ) {
	177	push @index_defs, create_index($index);
	178	}
	179
	180	#
	181	# Constraints
	182	#
	183	my $c_name_default = 'A';
	184	for my $c ( $table->get_constraints ) {
	185	next unless $c->type eq UNIQUE;
	186	push @constraint_defs, create_constraint($c);
	187	}
	188
4d438549	189	$create .= join(",\n", map { " $_" } @field_defs ) . "\n)";
bfb5a568	190
4d438549	191	return ($create, @index_defs, @constraint_defs, @trigger_defs );
bfb5a568	192	}
	193
	194	sub create_field
	195	{
	196	my ($field, $options) = @_;
	197
	198	my $field_name = $field->name;
	199	debug("PKG: Looking at field '$field_name'\n");
	200	my $field_comments = $field->comments
	201	? "-- " . $field->comments . "\n "
	202	: '';
	203
	204	my $field_def = $field_comments.$field_name;
	205
	206	# data type and size
	207	my $size = $field->size;
	208	my $data_type = $field->data_type;
	209	$data_type = 'varchar' if lc $data_type eq 'set';
	210	$data_type = 'blob' if lc $data_type eq 'bytea';
	211
	212	if ( lc $data_type =~ /(text\|blob)/i ) {
	213	$size = undef;
	214	}
	215
	216	# if ( $data_type =~ /timestamp/i ) {
	217	# push @trigger_defs,
	218	# "CREATE TRIGGER ts_${table_name} ".
	219	# "after insert on $table_name\n".
	220	# "begin\n".
	221	# " update $table_name set $field_name=timestamp() ".
	222	# "where id=new.id;\n".
	223	# "end;\n"
	224	# ;
	225	#
	226	# }
	227
	228	#
	229	# SQLite is generally typeless, but newer versions will
	230	# make a field autoincrement if it is declared as (and
	231	# only as) INTEGER PRIMARY KEY
	232	#
	233	my $pk = $field->table->primary_key;
	234	my @pk_fields = $pk ? $pk->fields : ();
	235
	236	if (
	237	$field->is_primary_key &&
	238	scalar @pk_fields == 1 &&
	239	(
	240	$data_type =~ /int(eger)?$/i
	241	\|\|
	242	( $data_type =~ /^number?$/i && $size !~ /,/ )
	243	)
	244	) {
	245	$data_type = 'INTEGER PRIMARY KEY';
	246	$size = undef;
	247	# $pk_set = 1;
	248	}
	249
	250	$field_def .= sprintf " %s%s", $data_type,
	251	( !$field->is_auto_increment && $size ) ? "($size)" : '';
	252
	253	# Null?
	254	$field_def .= ' NOT NULL' unless $field->is_nullable;
	255
256	# Default? XXX Need better quoting!
257	my $default = $field->default_value;
258	if ( defined $default ) {
259	if ( uc $default eq 'NULL') {
260	$field_def .= ' DEFAULT NULL';
261	} elsif ( $default eq 'now()' \|\|
262	$default eq 'CURRENT_TIMESTAMP' ) {
263	$field_def .= ' DEFAULT CURRENT_TIMESTAMP';
264	} elsif ( $default =~ /val\(/ ) {
265	next;
266	} else {
267	$field_def .= " DEFAULT '$default'";
268	}
269	}
270
271	return $field_def;
272
273	}
274
275	sub create_index
276	{
277	my ($index, $options) = @_;
278
279	my $name = $index->name;
4d438549	280	$name = mk_name($index->table->name, $name);
	281
	282	my $type = $index->type eq 'UNIQUE' ? "UNIQUE " : '';
bfb5a568	283
	284	# strip any field size qualifiers as SQLite doesn't like these
	285	my @fields = map { s/\(\d+\)$//; $_ } $index->fields;
	286	my $index_def =
4d438549	287	"CREATE ${type}INDEX $name ON " . $index->table->name .
4d438549	288	' (' . join( ', ', @fields ) . ')';
bfb5a568	289
	290	return $index_def;
	291	}
	292
	293	sub create_constraint
	294	{
	295	my ($c, $options) = @_;
	296
	297	my $name = $c->name;
4d438549	298	$name = mk_name($c->table->name, $name);
bfb5a568	299	my @fields = $c->fields;
	300
	301	my $c_def =
4d438549	302	"CREATE UNIQUE INDEX $name ON " . $c->table->name .
4d438549	303	' (' . join( ', ', @fields ) . ')';
bfb5a568	304
	305	return $c_def;
	306	}
	307
4d438549	308	sub alter_table { } # Noop
	309
	310	sub add_field {
	311	my ($field) = @_;
	312
	313	return sprintf("ALTER TABLE %s ADD COLUMN %s",
	314	$field->table->name, create_field($field))
	315	}
	316
	317	sub alter_create_index {
	318	my ($index) = @_;
	319
	320	# This might cause name collisions
	321	return create_index($index);
	322	}
	323
	324	sub alter_create_constraint {
	325	my ($constraint) = @_;
	326
	327	return create_constraint($constraint) if $constraint->type eq 'UNIQUE';
	328	}
	329
	330	sub alter_drop_constraint { alter_drop_index(@_) }
	331
	332	sub alter_drop_index {
	333	my ($constraint) = @_;
	334
	335	return sprintf("DROP INDEX %s ON %s",
	336	$constraint->name, $constraint->table->name);
	337	}
	338
	339	sub batch_alter_table {
	340	my ($table, $diffs) = @_;
	341
	342	$DB::single = 1 if $table->name eq 'deleted';
	343
	344	# If we have any of the following
	345	#
	346	# rename_field
	347	# alter_field
	348	# drop_field
	349	#
	350	# we need to do the following <http://www.sqlite.org/faq.html#q11>
	351	#
	352	# BEGIN TRANSACTION;
	353	# CREATE TEMPORARY TABLE t1_backup(a,b);
	354	# INSERT INTO t1_backup SELECT a,b FROM t1;
	355	# DROP TABLE t1;
	356	# CREATE TABLE t1(a,b);
	357	# INSERT INTO t1 SELECT a,b FROM t1_backup;
	358	# DROP TABLE t1_backup;
	359	# COMMIT;
	360	#
	361	# Fun, eh?
	362
	363	if ( @{$diffs->{rename_field}} == 0 &&
	364	@{$diffs->{alter_field}} == 0 &&
	365	@{$diffs->{drop_field}} == 0) {
	366	return join("\n", map {
	367	my $meth = __PACKAGE__->can($_) or die __PACKAGE__ . " cant $_";
	368	map { my $sql = $meth->(ref $_ eq 'ARRAY' ? @$_ : $_); $sql ? ("$sql;") : () } @{ $diffs->{$_} }
	369
	370	} grep { @{$diffs->{$_}} } keys %$diffs);
	371	}
372
373
374	my @sql;
375
376	do {
377	local $table->{name} = $table->name . '_temp_alter';
378	# We only want the table - dont care about indexes on tmp table
379	my ($table_sql) = create_table($table, {no_comments => 1, temporary_table => 1});
380	push @sql,$table_sql;
381	};
382
383	push @sql, "INSERT INTO @{[$table]}_temp_alter SELECT @{[ join(', ', $table->get_fields)]} FROM @{[$table]}",
384	"DROP TABLE @{[$table]}",
385	create_table($table, { no_comments => 1 }),
386	"INSERT INTO @{[$table]} SELECT @{[ join(', ', $table->get_fields)]} FROM @{[$table]}_temp_alter",
387	"DROP TABLE @{[$table]}_temp_alter";
388
389	return join(";\n", @sql, "");
390	}
391
392	sub drop_table {
393	my ($table) = @_;
394	return "DROP TABLE $table;";
395	}
396
bfb5a568	397	1;
758ab1cd	398
20770e44	399	=pod
	400
	401	=head1 SEE ALSO
	402
	403	SQL::Translator, http://www.sqlite.org/.
758ab1cd	404
	405	=head1 AUTHOR
	406
4d438549	407	Ken Y. Clark C<< <kclark@cpan.orgE> >>.
	408
	409	Diff code added by Ash Berlin C<< <ash@cpan.org> >>.
20770e44	410
20770e44	411	=cut