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

package SQL::Translator::Producer::Oracle;

# -------------------------------------------------------------------
# Copyright (C) 2002-2009 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::Oracle - Oracle SQL producer

=head1 SYNOPSIS

  use SQL::Translator;

  my $t = SQL::Translator->new( parser => '...', producer => 'Oracle' );
  print $translator->translate( $file );

=head1 DESCRIPTION

Creates an SQL DDL suitable for Oracle.

=head1 producer_args

=over

=item delay_constraints

This option remove the primary key and other key constraints from the
CREATE TABLE statement and adds ALTER TABLEs at the end with it.

=item quote_field_names

Controls whether quotes are being used around column names in generated DDL.

=item quote_table_names

Controls whether quotes are being used around table, sequence and trigger names in
generated DDL.

=back

=head1 NOTES

=head2 Autoincremental primary keys

This producer uses sequences and triggers to autoincrement primary key
columns, if necessary. SQLPlus and DBI expect a slightly different syntax
of CREATE TRIGGER statement. You might have noticed that this
producer returns a scalar containing all statements concatenated by
newlines or an array of single statements depending on the context
(scalar, array) it has been called in.

SQLPlus expects following trigger syntax:

    CREATE OR REPLACE TRIGGER ai_person_id
    BEFORE INSERT ON person
    FOR EACH ROW WHEN (
     new.id IS NULL OR new.id = 0
    )
    BEGIN
     SELECT sq_person_id.nextval
     INTO :new.id
     FROM dual;
    END;
    /

Whereas if you want to create the same trigger using L<DBI/do>, you need
to omit the last slash:

    my $dbh = DBI->connect('dbi:Oracle:mysid', 'scott', 'tiger');
    $dbh->do("
        CREATE OR REPLACE TRIGGER ai_person_id
        BEFORE INSERT ON person
        FOR EACH ROW WHEN (
         new.id IS NULL OR new.id = 0
        )
        BEGIN
         SELECT sq_person_id.nextval
         INTO :new.id
         FROM dual;
        END;
    ");

If you call this producer in array context, we expect you want to process
the returned array of statements using L<DBI> like
L<DBIx::Class::Schema/deploy> does.

To get this working we removed the slash in those statements in version
0.09002 of L<SQL::Translator> when called in array context. In scalar
context the slash will be still there to ensure compatibility with SQLPlus.

=cut

use strict;
use vars qw[ $VERSION $DEBUG $WARN ];
$VERSION = '1.59';
$DEBUG   = 0 unless defined $DEBUG;

use SQL::Translator::Schema::Constants;
use SQL::Translator::Utils qw(header_comment);

my %translate  = (
    #
    # MySQL types
    #
    bigint     => 'number',
    double     => 'float',
    decimal    => 'number',
    float      => 'float',
    int        => 'number',
    integer    => 'number',
    mediumint  => 'number',
    smallint   => 'number',
    tinyint    => 'number',
    char       => 'char',
    varchar    => 'varchar2',
    tinyblob   => 'blob',
    blob       => 'blob',
    mediumblob => 'blob',
    longblob   => 'blob',
    tinytext   => 'varchar2',
    text       => 'clob',
    longtext   => 'clob',
    mediumtext => 'clob',
    enum       => 'varchar2',
    set        => 'varchar2',
    date       => 'date',
    datetime   => 'date',
    time       => 'date',
    timestamp  => 'date',
    year       => 'date',

    #
    # PostgreSQL types
    #
    numeric             => 'number',
    'double precision'  => 'number',
    serial              => 'number',
    bigserial           => 'number',
    money               => 'number',
    character           => 'char',
    'character varying' => 'varchar2',
    bytea               => 'BLOB',
    interval            => 'number',
    boolean             => 'number',
    point               => 'number',
    line                => 'number',
    lseg                => 'number',
    box                 => 'number',
    path                => 'number',
    polygon             => 'number',
    circle              => 'number',
    cidr                => 'number',
    inet                => 'varchar2',
    macaddr             => 'varchar2',
    bit                 => 'number',
    'bit varying'       => 'number',

    #
    # Oracle types
    #
    number              => 'number',
    varchar2            => 'varchar2',
    long                => 'clob',
);

#
# Oracle 8/9 max size of data types from:
# http://www.ss64.com/orasyntax/datatypes.html
#
my %max_size = (
    char      => 2000,
    float     => 126,
    nchar     => 2000,
    nvarchar2 => 4000,
    number    => [ 38, 127 ],
    raw       => 2000,
    varchar   => 4000,          # only synonym for varchar2
    varchar2  => 4000,
);

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

# Quote used to escape table, field, sequence and trigger names
my $quote_char  = '"';

# -------------------------------------------------------------------
sub produce {
    my $translator     = shift;
    $DEBUG             = $translator->debug;
    $WARN              = $translator->show_warnings || 0;
    my $no_comments    = $translator->no_comments;
    my $add_drop_table = $translator->add_drop_table;
    my $schema         = $translator->schema;
    my $oracle_version  = $translator->producer_args->{oracle_version} || 0;
    my $delay_constraints = $translator->producer_args->{delay_constraints};
    my ($output, $create, @table_defs, @fk_defs, @trigger_defs, @index_defs, @constraint_defs);

    $create .= header_comment unless ($no_comments);
    my $qt = 1 if $translator->quote_table_names;
    my $qf = 1 if $translator->quote_field_names;

    if ( $translator->parser_type =~ /mysql/i ) {
        $create .= 
            "-- We assume that default NLS_DATE_FORMAT has been changed\n".
            "-- but we set it here anyway to be self-consistent.\n"
            unless $no_comments;

        $create .= 
        "ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';\n\n";
    }

    for my $table ( $schema->get_tables ) { 
        my ( $table_def, $fk_def, $trigger_def, $index_def, $constraint_def ) = create_table(
            $table,
            {
                add_drop_table    => $add_drop_table,
                show_warnings     => $WARN,
                no_comments       => $no_comments,
                delay_constraints => $delay_constraints,
                quote_table_names => $qt,
                quote_field_names => $qf,
            }
        );
        push @table_defs, @$table_def;
        push @fk_defs, @$fk_def;
        push @trigger_defs, @$trigger_def;
        push @index_defs, @$index_def;
        push @constraint_defs, @$constraint_def;
    }

    my (@view_defs);
    foreach my $view ( $schema->get_views ) {
        my ( $view_def ) = create_view(
            $view,
            {
                add_drop_view     => $add_drop_table,
                quote_table_names => $qt,
            }
        );
        push @view_defs, @$view_def;
    }

    if (wantarray) {
        return defined $create ? $create : (), @table_defs, @view_defs, @fk_defs, @trigger_defs, @index_defs, @constraint_defs;
    }
    else {
        $create .= join (";\n\n", @table_defs, @view_defs, @fk_defs, @index_defs, @constraint_defs);
        $create .= ";\n\n";
        # If wantarray is not set we have to add "/" in this statement
        # DBI->do() needs them omitted
        # triggers may NOT end with a semicolon
        $create .= join "/\n\n", @trigger_defs;
        # for last trigger
        $create .= "/\n\n";
        return $create;
    }
}

sub create_table {
    my ($table, $options) = @_;
    my $qt = $options->{quote_table_names};
    my $qf = $options->{quote_field_names};
    my $table_name = $table->name;
    my $table_name_q = quote($table_name,$qt);

    my $item = '';
    my $drop;
    my (@create, @field_defs, @constraint_defs, @fk_defs, @trigger_defs);

    push @create, "--\n-- Table: $table_name\n--" unless $options->{no_comments};
    push @create, qq[DROP TABLE $table_name_q CASCADE CONSTRAINTS] if $options->{add_drop_table};

        my ( %field_name_scope, @field_comments );
        for my $field ( $table->get_fields ) {
            my ($field_create, $field_defs, $trigger_defs, $field_comments) =
              create_field($field, $options, \%field_name_scope);
            push @create, @$field_create if ref $field_create;
            push @field_defs, @$field_defs if ref $field_defs;
            push @trigger_defs, @$trigger_defs if ref $trigger_defs;
            push @field_comments, @$field_comments if ref $field_comments;
        }

        #
        # Table options
        #
        my @table_options;
        for my $opt ( $table->options ) {
            if ( ref $opt eq 'HASH' ) {
                my ( $key, $value ) = each %$opt;
                if ( ref $value eq 'ARRAY' ) {
                    push @table_options, "$key\n(\n".  join ("\n",
                        map { "  $_->[0]\t$_->[1]" } 
                        map { [ each %$_ ] }
                        @$value
                    )."\n)";
                }
                elsif ( !defined $value ) {
                    push @table_options, $key;
                }
                else {
                    push @table_options, "$key    $value";
                }
            }
        }

        #
        # Table constraints
        #
        for my $c ( $table->get_constraints ) {
            my $name    = $c->name || '';
            my @fields  = map { quote($_,$qf) } $c->fields;
            my @rfields = quote($c->reference_fields,$qf);
            next if !@fields && $c->type ne CHECK_C;

            if ( $c->type eq PRIMARY_KEY ) {
                # create a name if delay_constraints
                $name ||= mk_name( $table_name, 'pk' )
                  if $options->{delay_constraints};
                $name = quote($name,$qf);
                push @constraint_defs, ($name ? "CONSTRAINT $name " : '') .
                  'PRIMARY KEY (' . join( ', ', @fields ) . ')';
            }
            elsif ( $c->type eq UNIQUE ) {
              # Don't create UNIQUE constraints identical to the primary key
              if ( my $pk = $table->primary_key ) {
                my $u_fields = join(":", @fields);
                my $pk_fields = join(":", $pk->fields);
                next if $u_fields eq $pk_fields;
              }

              if ($name) {
                # Force prepend of table_name as ORACLE doesn't allow duplicate
                # CONSTRAINT names even for different tables (ORA-02264)
                $name = mk_name( "${table_name}_$name", 'u' ) unless $name =~ /^$table_name/;
              }
              else {
                $name = mk_name( $table_name, 'u' );
              }

              $name = quote($name, $qf);

                for my $f ( $c->fields ) {
                    my $field_def = $table->get_field( $f ) or next;
                    my $dtype     = $translate{ ref $field_def->data_type eq "ARRAY" ? $field_def->data_type->[0] : $field_def->data_type} or next;
                    if ( $WARN && $dtype =~ /clob/i ) {
                        warn "Oracle will not allow UNIQUE constraints on " .
                             "CLOB field '" . $field_def->table->name . '.' .
                             $field_def->name . ".'\n"
                    }
                }

                push @constraint_defs, "CONSTRAINT $name UNIQUE " .
                    '(' . join( ', ', @fields ) . ')';
            }
            elsif ( $c->type eq CHECK_C ) {
                $name ||= mk_name( $name || $table_name, 'ck' );
                $name = quote($name, $qf);
                my $expression = $c->expression || '';
                push @constraint_defs, "CONSTRAINT $name CHECK ($expression)";
            }
            elsif ( $c->type eq FOREIGN_KEY ) {
                $name = mk_name( join('_', $table_name, $c->fields). '_fk' );
                $name = quote($name, $qf);
                my $def = "CONSTRAINT $name FOREIGN KEY ";

                if ( @fields ) {
                    $def .= '(' . join( ', ', @fields ) . ')';
                }

                my $ref_table = quote($c->reference_table,$qt);

                $def .= " REFERENCES $ref_table";

                if ( @rfields ) {
                    $def .= ' (' . join( ', ', @rfields ) . ')';
                }

                if ( $c->match_type ) {
                    $def .= ' MATCH ' . 
                        ( $c->match_type =~ /full/i ) ? 'FULL' : 'PARTIAL';
                }

                if ( $c->on_delete ) {
                    $def .= ' ON DELETE '.join( ' ', $c->on_delete );
                }

                # disabled by plu 2007-12-29 - doesn't exist for oracle
                #if ( $c->on_update ) {
                #    $def .= ' ON UPDATE '.join( ' ', $c->on_update );
                #}

                push @fk_defs, sprintf("ALTER TABLE %s ADD %s", $table_name_q, $def);
            }
        }

        #
        # Index Declarations
        #
        my @index_defs = ();
        for my $index ( $table->get_indices ) {
            my $index_name = $index->name || '';
            my $index_type = $index->type || NORMAL;
            my @fields     = map { quote($_, $qf) } $index->fields;
            next unless @fields;

            my @index_options;
            for my $opt ( $index->options ) {
                if ( ref $opt eq 'HASH' ) {
                    my ( $key, $value ) = each %$opt;
                    if ( ref $value eq 'ARRAY' ) {
                        push @table_options, "$key\n(\n".  join ("\n",
                            map { "  $_->[0]\t$_->[1]" } 
                            map { [ each %$_ ] }
                           @$value
                        )."\n)";
                    }
                    elsif ( !defined $value ) {
                        push @index_options, $key;
                    }
                    else {
                        push @index_options, "$key    $value";
                    }
                }
            }
            my $index_options = @index_options
              ? "\n".join("\n", @index_options) : '';

            if ( $index_type eq PRIMARY_KEY ) {
                $index_name = $index_name ? mk_name( $index_name ) 
                    : mk_name( $table_name, 'pk' );
                $index_name = quote($index_name, $qf);
                push @field_defs, 'CONSTRAINT '.$index_name.' PRIMARY KEY '.
                    '(' . join( ', ', @fields ) . ')';
            }
            elsif ( $index_type eq NORMAL ) {
                $index_name = $index_name ? mk_name( $index_name ) 
                    : mk_name( $table_name, $index_name || 'i' );
                $index_name = quote($index_name, $qf);
                push @index_defs, 
                    "CREATE INDEX $index_name on $table_name_q (".
                        join( ', ', @fields ).  
                    ")$index_options";
            }
            elsif ( $index_type eq UNIQUE ) {
                $index_name = $index_name ? mk_name( $index_name ) 
                    : mk_name( $table_name, $index_name || 'i' );
                $index_name = quote($index_name, $qf);
                push @index_defs, 
                    "CREATE UNIQUE INDEX $index_name on $table_name_q (".
                        join( ', ', @fields ).  
                    ")$index_options"; 
            }
            else {
                warn "Unknown index type ($index_type) on table $table_name.\n"
                    if $WARN;
            }
        }

        if ( my @table_comments = $table->comments ) {
            for my $comment ( @table_comments ) {
                next unless $comment;
                $comment =~ s/'/''/g;
                push @field_comments, "COMMENT ON TABLE $table_name_q is\n '".
                $comment . "'" unless $options->{no_comments}
                ;
            }
        }

        my $table_options = @table_options 
            ? "\n".join("\n", @table_options) : '';
    push @create, "CREATE TABLE $table_name_q (\n" .
            join( ",\n", map { "  $_" } @field_defs,
            ($options->{delay_constraints} ? () : @constraint_defs) ) .
            "\n)$table_options";

    @constraint_defs = map { "ALTER TABLE $table_name_q ADD $_"  }
      @constraint_defs;

    if ( $WARN ) {
        if ( %truncated ) {
            warn "Truncated " . keys( %truncated ) . " names:\n";
            warn "\t" . join( "\n\t", sort keys %truncated ) . "\n";
        }
    }

    return \@create, \@fk_defs, \@trigger_defs, \@index_defs, ($options->{delay_constraints} ? \@constraint_defs : []);
}

sub alter_field {
    my ($from_field, $to_field, $options) = @_;

    my $qt = $options->{quote_table_names};
    my ($field_create, $field_defs, $trigger_defs, $field_comments) =
      create_field($to_field, $options, {});

    # Fix ORA-01442
    if ($to_field->is_nullable && !$from_field->is_nullable) {
        die 'Cannot remove NOT NULL from table field';
    } elsif (!$from_field->is_nullable && !$to_field->is_nullable) {
        @$field_defs = map { s/ NOT NULL//; $_} @$field_defs;
    }

    my $table_name = quote($to_field->table->name,$qt);

    return 'ALTER TABLE '.$table_name.' MODIFY ( '.join('', @$field_defs).' )';
}

sub add_field {
    my ($new_field, $options) = @_;

    my $qt = $options->{quote_table_names};
    my ($field_create, $field_defs, $trigger_defs, $field_comments) =
      create_field($new_field, $options, {});

    my $table_name = quote($new_field->table->name,$qt);

    my $out = sprintf('ALTER TABLE %s ADD ( %s )',
                      $table_name,
                      join('', @$field_defs));
    return $out;
}

sub create_field {
    my ($field, $options, $field_name_scope) = @_;
    my $qf = $options->{quote_field_names};
    my $qt = $options->{quote_table_names};

    my (@create, @field_defs, @trigger_defs, @field_comments);

    my $table_name = $field->table->name;
    my $table_name_q = quote($table_name, $qt);

    #
    # Field name
    #
    my $field_name    = mk_name(
                                $field->name, '', $field_name_scope, 1
                               );
    my $field_name_q = quote($field_name, $qf);
    my $field_def     = quote($field_name, $qf);
    $field->name( $field_name );

    #
    # Datatype
    #
    my $check;
    my $data_type = lc $field->data_type;
    my @size      = $field->size;
    my %extra     = $field->extra;
    my $list      = $extra{'list'} || [];
    # \todo deal with embedded quotes
    my $commalist = join( ', ', map { qq['$_'] } @$list );

    if ( $data_type eq 'enum' ) {
        $check = "CHECK ($field_name_q IN ($commalist))";
        $data_type = 'varchar2';
    }
    elsif ( $data_type eq 'set' ) {
        # XXX add a CHECK constraint maybe 
        # (trickier and slower, than enum :)
        $data_type = 'varchar2';
    }
    else {
      if (defined $translate{ $data_type }) {
        if (ref $translate{ $data_type } eq "ARRAY") {
          ($data_type,$size[0])  = @{$translate{ $data_type }};
        } else {
          $data_type  = $translate{ $data_type };
        }
      }
      $data_type ||= 'varchar2';
    }

    # ensure size is not bigger than max size oracle allows for data type
    if ( defined $max_size{$data_type} ) {
        for ( my $i = 0 ; $i < scalar @size ; $i++ ) {
            my $max =
              ref( $max_size{$data_type} ) eq 'ARRAY'
              ? $max_size{$data_type}->[$i]
              : $max_size{$data_type};
            $size[$i] = $max if $size[$i] > $max;
        }
    }

    #
    # Fixes ORA-02329: column of datatype LOB cannot be 
    # unique or a primary key
    #
    if ( $data_type eq 'clob' && $field->is_primary_key ) {
        $data_type = 'varchar2';
        $size[0]   = 4000;
        warn "CLOB cannot be a primary key, changing to VARCHAR2\n"
          if $WARN;
    }

    if ( $data_type eq 'clob' && $field->is_unique ) {
        $data_type = 'varchar2';
        $size[0]   = 4000;
        warn "CLOB cannot be a unique key, changing to VARCHAR2\n"
          if $WARN;
    }

    #
    # Fixes ORA-00907: missing right parenthesis
    #
    if ( $data_type =~ /(date|clob)/i ) {
        undef @size;
    }

    #
    # Fixes ORA-00906: missing right parenthesis
		# if size is 0 or undefined
    #
    for (qw/varchar2/) {
        if ( $data_type =~ /^($_)$/i ) {
            $size[0] ||= $max_size{$_};
        }
    }

    $field_def .= " $data_type";
    if ( defined $size[0] && $size[0] > 0 ) {
        $field_def .= '(' . join( ',', @size ) . ')';
    }

    #
    # Default value
    #
    my $default = $field->default_value;
    if ( defined $default ) {
        #
        # Wherein we try to catch a string being used as 
        # a default value for a numerical field.  If "true/false,"
        # then sub "1/0," otherwise just test the truthity of the
        # argument and use that (naive?).
        #
        if (ref $default and defined $$default) {
          $default = $$default;
        } elsif (ref $default) {
          $default = 'NULL';
        } elsif ( 
            $data_type =~ /^number$/i && 
            $default   !~ /^-?\d+$/     &&
            $default   !~ m/null/i
           ) {
            if ( $default =~ /^true$/i ) {
                $default = "'1'";
            } elsif ( $default =~ /^false$/i ) {
                $default = "'0'";
            } else {
                $default = $default ? "'1'" : "'0'";
            }
        } elsif ( 
                 $data_type =~ /date/ && (
                                          $default eq 'current_timestamp' 
                                          ||
                                          $default eq 'now()' 
                                         )
                ) {
            $default = 'SYSDATE';
        } else {
            $default = $default =~ m/null/i ? 'NULL' : "'$default'"
        } 

        $field_def .= " DEFAULT $default",
    }

    #
    # Not null constraint
    #
    unless ( $field->is_nullable ) {
        $field_def .= ' NOT NULL';
    }

    $field_def .= " $check" if $check;

    #
    # Auto_increment
    #
    if ( $field->is_auto_increment ) {
        my $base_name    = $table_name . "_". $field_name;
        my $seq_name     = quote(mk_name( $base_name, 'sq' ),$qt);
        my $trigger_name = quote(mk_name( $base_name, 'ai' ),$qt);

        push @create, qq[DROP SEQUENCE $seq_name] if $options->{add_drop_table};
        push @create, "CREATE SEQUENCE $seq_name";
        my $trigger =
          "CREATE OR REPLACE TRIGGER $trigger_name\n" .
          "BEFORE INSERT ON $table_name_q\n" .
          "FOR EACH ROW WHEN (\n" .
          " new.$field_name_q IS NULL".
          " OR new.$field_name_q = 0\n".
          ")\n".
          "BEGIN\n" .
          " SELECT $seq_name.nextval\n" .
          " INTO :new." . $field_name_q."\n" .
          " FROM dual;\n" .
          "END;\n";

        push @trigger_defs, $trigger;
    }

    if ( lc $field->data_type eq 'timestamp' ) {
        my $base_name = $table_name . "_". $field_name;
        my $trig_name = quote(mk_name( $base_name, 'ts' ), $qt);
        my $trigger = 
          "CREATE OR REPLACE TRIGGER $trig_name\n".
          "BEFORE INSERT OR UPDATE ON $table_name_q\n".
          "FOR EACH ROW WHEN (new.$field_name_q IS NULL)\n".
          "BEGIN \n".
          " SELECT sysdate INTO :new.$field_name_q FROM dual;\n".
          "END;\n";

          push @trigger_defs, $trigger;
    }

    push @field_defs, $field_def;

    if ( my $comment = $field->comments ) {
        $comment =~ s/'/''/g;
        push @field_comments, 
          "COMMENT ON COLUMN $table_name_q.$field_name_q is\n '" .
            $comment . "';" unless $options->{no_comments};
    }

    return \@create, \@field_defs, \@trigger_defs, \@field_comments;

}


sub create_view {
    my ($view, $options) = @_;
    my $qt = $options->{quote_table_names};
    my $view_name = quote($view->name,$qt);
    
    my @create;
    push @create, qq[DROP VIEW $view_name]
        if $options->{add_drop_view};

    push @create, sprintf("CREATE VIEW %s AS\n%s",
                      $view_name,
                      $view->sql);

    return \@create;
}

# -------------------------------------------------------------------
sub mk_name {
    my $basename      = shift || ''; 
    my $type          = shift || ''; 
       $type          = '' if $type =~ /^\d/;
    my $scope         = shift || ''; 
    my $critical      = shift || '';
    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 = $name;
        substr($name, $max_id_length - 2) = ""
            if length( $name ) >= $max_id_length - 1;
        $name        .= sprintf( "%02d", $prev++ );

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

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

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

1;

# -------------------------------------------------------------------
sub quote {
  my ($name, $q) = @_;
  $q && $name ? "$quote_char$name$quote_char" : $name;
}


# -------------------------------------------------------------------
# All bad art is the result of good intentions.
# Oscar Wilde
# -------------------------------------------------------------------

=pod

=head1 CREDITS

Mad props to Tim Bunce for much of the logic stolen from his "mysql2ora"
script.

=head1 AUTHORS

Ken Youens-Clark E<lt>kclark@cpan.orgE<gt>,
Alexander Hartmaier E<lt>abraxxa@cpan.orgE<gt>,
Fabien Wernli E<lt>faxmodem@cpan.orgE<gt>.

=head1 SEE ALSO

SQL::Translator, DDL::Oracle, mysql2ora.

=cut