# File lib/active_record/postgresql_extensions/tables.rb, line 313 def primary_key_constraint(columns, options = {}) table_constraints << PostgreSQLPrimaryKeyConstraint.new(@base, columns, options) end
class ActiveRecord::ConnectionAdapters::PostgreSQLTableDefinition
Creates a PostgreSQL table definition. This class isn’t really meant to be used directly. Instead, see PostgreSQLAdapter#create_table
for usage.
Beyond our various PostgreSQL-specific extensions, we’ve also added the post_processing
member, which allows you to tack on some SQL statements to run after creating the table. This member should be an Array of SQL statements to run once the table has been created. See the source code for PostgreSQLAdapter#create_table
and PostgreSQLTableDefinition#geometry
for an example of its use.
Constants
- LIKE_TYPES
Attributes
Public Instance Methods
Add a CHECK constraint to the table. See PostgreSQLCheckConstraint
for more details.
# File lib/active_record/postgresql_extensions/tables.rb, line 291 def check_constraint(expression, options = {}) table_constraints << PostgreSQLCheckConstraint.new(@base, expression, options) end
Add an EXCLUDE constraint to the table. See PostgreSQLExcludeConstraint
for more details.
# File lib/active_record/postgresql_extensions/tables.rb, line 309 def exclude(excludes, options = {}) table_constraints << PostgreSQLExcludeConstraint.new(@base, table_name, excludes, options) end
Add a FOREIGN KEY constraint to the table. See PostgreSQLForeignKeyConstraint
for more details.
# File lib/active_record/postgresql_extensions/tables.rb, line 303 def foreign_key(columns, ref_table, *args) table_constraints << PostgreSQLForeignKeyConstraint.new(@base, columns, ref_table, *args) end
# File lib/active_record/postgresql_extensions/geometry.rb, line 328 def geography(column_name, opts = {}) opts = { :srid => ActiveRecord::PostgreSQLExtensions::PostGIS.UNKNOWN_SRIDS[:geography] }.merge(opts) self.spatial(column_name, opts.merge( :spatial_column_type => :geography )) end
Add an INDEX to the table. This INDEX will be added during post processing after the table has been created. See PostgreSQLIndexDefinition
for more details.
# File lib/active_record/postgresql_extensions/tables.rb, line 377 def index(name, columns, options = {}) post_processing << PostgreSQLIndexDefinition.new(@base, name, self.table_name, columns, options) end
Creates a LIKE statement for use in a table definition.
Options¶ ↑
-
:including
and:excluding
- set options for the INCLUDING and EXCLUDING clauses in a LIKE statement. Valid values are:constraints
,:defaults
and:indexes
. You can set one or more by using an Array.
See the PostgreSQL documentation for details on how to use LIKE. Be sure to take note as to how it differs from INHERITS.
Also, be sure to note that, like, this LIKE isn’t, like, the LIKE you use in a WHERE condition. This is, PostgreSQL’s own special LIKE clause for table definitions. Like.
# File lib/active_record/postgresql_extensions/tables.rb, line 271 def like(parent_table, options = {}) assert_valid_like_types(options[:includes]) assert_valid_like_types(options[:excludes]) # Huh? Whyfor I dun this? # @like = base.with_schema(@schema) { "LIKE #{base.quote_table_name(parent_table)}" } @like = "LIKE #{@base.quote_table_name(parent_table)}" if options[:including] @like << Array.wrap(options[:including]).collect { |l| " INCLUDING #{l.to_s.upcase}" }.join end if options[:excluding] @like << Array.wrap(options[:excluding]).collect { |l| " EXCLUDING #{l.to_s.upcase}" }.join end @like end
Add statements to execute to after a table has been created.
# File lib/active_record/postgresql_extensions/tables.rb, line 382 def post_processing @post_processing ||= [] end
This is a special spatial type for the PostGIS extension’s data types. It is used in a table definition to define a spatial column.
Depending on the version of PostGIS being used, we’ll try to create geometry columns in a post-2.0-ish, typmod-based way or a pre-2.0-ish AddGeometryColumn-based way. We can also add CHECK constraints and create a GiST index on the column all in one go.
In versions of PostGIS prior to 2.0, geometry columns are created using the AddGeometryColumn and will created with CHECK constraints where appropriate and entries to the geometry_columns
will be updated accordingly.
In versions of PostGIS after 2.0, geometry columns are creating using typmod specifiers. CHECK constraints can still be created, but their creation must be forced using the :force_constraints
option.
The geometry
and geography
methods are shortcuts to calling the spatial
method with the :spatial_column_type
option set accordingly.
Options¶ ↑
-
:spatial_column_type
- the column type. This value can be one of:geometry
or:geography
. This value doesn’t refer to the spatial type used by the column, but rather by the actual column type itself. -
:geometry_type
- set the geometry type. The actual data type is either “geometry” or “geography”; this option refers to the spatial type being used, i.e. “POINT”, “POLYGON”, “” -
:add_constraints
- automatically creates the CHECK constraints used to enforce ndims, srid and geometry type. The default is true. -
:force_constraints
- forces the creation of CHECK constraints in versions of PostGIS post-2.0. -
:add_geometry_columns_entry
- automatically adds an entry to thegeometry_columns
table. We will try to delete any existing match ingeometry_columns
before inserting. The default is true. This value is ignored in versions of PostGIS post-2.0. -
:create_gist_index
- automatically creates a GiST index for the new geometry column. This option accepts either a true/false expression or a String. If the value is a String, we’ll use it as the index name. The default is true. -
:ndims
- the number of dimensions to allow in the geometry. This value is either 2 or 3 by default depending on the value of the:geometry_type
option. If the:geometry_type
ends in an “m” (for “measured geometries” the default is 3); for everything else, it is 2. -
:srid
- the SRID, a.k.a. the Spatial Reference Identifier. The default depends on the version of PostGIS being used and the spatial column type being used. Refer to the PostGIS docs for the specifics, but generally this means either a value of -1 for versions of PostGIS prior to 2.0 for geometry columns and a value of 0 for versions post-2.0 and for all geography columns.
# File lib/active_record/postgresql_extensions/geometry.rb, line 313 def spatial(column_name, opts = {}) column = self[column_name] || PostgreSQLGeometryColumnDefinition.new(base, column_name, opts) unless @columns.include?(column) @columns << column end table_constraints.concat(column.table_constraints) post_processing.concat(column.geometry_columns_entry(table_name)) post_processing.concat(column.geometry_column_index(table_name)) self end
Add a UNIQUE constraint to the table. See PostgreSQLUniqueConstraint
for more details.
# File lib/active_record/postgresql_extensions/tables.rb, line 297 def unique_constraint(columns, options = {}) table_constraints << PostgreSQLUniqueConstraint.new(@base, columns, options) end
Private Instance Methods
# File lib/active_record/postgresql_extensions/tables.rb, line 389 def table_constraints @table_constraints ||= [] end