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SQL::Translator::Schema::Constraint(3) User Contributed Perl Documentation SQL::Translator::Schema::Constraint(3)

NAME

SQL::Translator::Schema::Constraint - SQL::Translator constraint object

SYNOPSIS

  use SQL::Translator::Schema::Constraint;
  my $constraint = SQL::Translator::Schema::Constraint->new(
      name   => 'foo',
      fields => [ id ],
      type   => PRIMARY_KEY,
  );

DESCRIPTION

"SQL::Translator::Schema::Constraint" is the constraint object.

METHODS

new

Object constructor.

  my $schema           =  SQL::Translator::Schema::Constraint->new(
      table            => $table,        # table to which it belongs
      type             => 'foreign_key', # type of table constraint
      name             => 'fk_phone_id', # name of the constraint
      fields           => 'phone_id',    # field in the referring table
      reference_fields => 'phone_id',    # referenced field
      reference_table  => 'phone',       # referenced table
      match_type       => 'full',        # how to match
      on_delete        => 'cascade',     # what to do on deletes
      on_update        => '',            # what to do on updates
  );

deferrable

Get or set whether the constraint is deferrable. If not defined, then returns "1." The argument is evaluated by Perl for True or False, so the following are equivalent:

  $deferrable = $field->deferrable(0);
  $deferrable = $field->deferrable('');
  $deferrable = $field->deferrable('0');

expression

Gets and set the expression used in a CHECK constraint.

  my $expression = $constraint->expression('...');

is_valid

Determine whether the constraint is valid or not.

  my $ok = $constraint->is_valid;

fields

Gets and set the fields the constraint is on. Accepts a string, list or arrayref; returns an array or array reference. Will unique the field names and keep them in order by the first occurrence of a field name.

The fields are returned as Field objects if they exist or as plain names if not. (If you just want the names and want to avoid the Field's overload magic use "field_names").

Returns undef or an empty list if the constraint has no fields set.

  $constraint->fields('id');
  $constraint->fields('id', 'name');
  $constraint->fields( 'id, name' );
  $constraint->fields( [ 'id', 'name' ] );
  $constraint->fields( qw[ id name ] );
  my @fields = $constraint->fields;

field_names

Read-only method to return a list or array ref of the field names. Returns undef or an empty list if the constraint has no fields set. Useful if you want to avoid the overload magic of the Field objects returned by the fields method.

  my @names = $constraint->field_names;

match_type

Get or set the constraint's match_type. Only valid values are "full" "partial" and "simple"

  my $match_type = $constraint->match_type('FULL');

name

Get or set the constraint's name.

  my $name = $constraint->name('foo');

options

Gets or adds to the constraints's options (e.g., "INITIALLY IMMEDIATE"). Returns an array or array reference.

  $constraint->options('NORELY');
  my @options = $constraint->options;

on_delete

Get or set the constraint's "on delete" action.

  my $action = $constraint->on_delete('cascade');

on_update

Get or set the constraint's "on update" action.

  my $action = $constraint->on_update('no action');

reference_fields

Gets and set the fields in the referred table. Accepts a string, list or arrayref; returns an array or array reference.

  $constraint->reference_fields('id');
  $constraint->reference_fields('id', 'name');
  $constraint->reference_fields( 'id, name' );
  $constraint->reference_fields( [ 'id', 'name' ] );
  $constraint->reference_fields( qw[ id name ] );
  my @reference_fields = $constraint->reference_fields;

reference_table

Get or set the table referred to by the constraint.

  my $reference_table = $constraint->reference_table('foo');

table

Get or set the constraint's table object.

  my $table = $field->table;

type

Get or set the constraint's type.

  my $type = $constraint->type( PRIMARY_KEY );

equals

Determines if this constraint is the same as another

  my $isIdentical = $constraint1->equals( $constraint2 );

AUTHOR

Ken Youens-Clark <kclark@cpan.org>.

2024-03-08 perl v5.40.0