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SQL::Translator::Parser::DBI - "parser" for DBI handles


  use DBI;
  use SQL::Translator;

  my $dbh = DBI->connect('dsn', 'user', 'pass',
          RaiseError       => 1,
          FetchHashKeyName => 'NAME_lc',

  my $translator  =  SQL::Translator->new(
      parser      => 'DBI',
      parser_args => {
          dbh => $dbh,


  use SQL::Translator;

  my $translator      =  SQL::Translator->new(
      parser          => 'DBI',
      parser_args     => {
          dsn         => 'dbi:mysql:FOO',
          db_user     => 'guest',
          db_password => 'password',


This parser accepts an open database handle (or the arguments to create one) and queries the database directly for the information.

The following are acceptable arguments:

  • dbh

    An open DBI database handle. NB: Be sure to create the database with the "FetchHashKeyName => 'NAME_lc'" option as all the DBI parsers expect lowercased column names.

  • dsn

    The DSN to use for connecting to a database.

  • db_user

    The user name to use for connecting to a database.

  • db_password

    The password to use for connecting to a database.

There is no need to specify which type of database you are querying as this is determined automatically by inspecting $dbh->{'Driver'}{'Name'}. If a parser exists for your database, it will be used automatically; if not, the code will fail automatically (and you can write the parser and contribute it to the project!).

Currently parsers exist for the following databases:

  • MySQL

  • SQLite

  • Sybase

  • PostgreSQL (still experimental)

Most of these parsers are able to query the database directly for the structure rather than parsing a text file. For large schemas, this is probably orders of magnitude faster than traditional parsing (which uses Parse::RecDescent, an amazing module but really quite slow).

Though no Oracle parser currently exists, it would be fairly easy to query an Oracle database directly by using DDL::Oracle to generate a DDL for the schema and then using the normal Oracle parser on this. Perhaps future versions of SQL::Translator will include the ability to query Oracle directly and skip the parsing of a text file, too.


Ken Y. Clark <>.


DBI, SQL::Translator.