module Sequel::Postgres::EnumDatabaseMethods

Methods enabling Database object integration with enum types.

Public Class Methods

extended(db) click to toggle source

Parse the available enum values when loading this extension into your database.

   # File lib/sequel/extensions/pg_enum.rb
69 def self.extended(db)
70   db.instance_exec do
71     @enum_labels = {}
72     parse_enum_labels
73   end
74 end

Public Instance Methods

add_enum_value(enum, value, opts=OPTS) click to toggle source

Run the SQL to add the given value to the existing enum type. Options:

:after

Add the new value after this existing value.

:before

Add the new value before this existing value.

:if_not_exists

Do not raise an error if the value already exists in the enum.

   # File lib/sequel/extensions/pg_enum.rb
81 def add_enum_value(enum, value, opts=OPTS)
82   sql = String.new
83   sql << "ALTER TYPE #{quote_schema_table(enum)} ADD VALUE#{' IF NOT EXISTS' if opts[:if_not_exists]} #{literal(value.to_s)}"
84   if v = opts[:before]
85     sql << " BEFORE #{literal(v.to_s)}"
86   elsif v = opts[:after]
87     sql << " AFTER #{literal(v.to_s)}"
88   end
89   run sql
90   parse_enum_labels
91   nil
92 end
create_enum(enum, values) click to toggle source

Run the SQL to create an enum type with the given name and values.

    # File lib/sequel/extensions/pg_enum.rb
 95 def create_enum(enum, values)
 96   sql = "CREATE TYPE #{quote_schema_table(enum)} AS ENUM (#{values.map{|v| literal(v.to_s)}.join(', ')})"
 97   run sql
 98   parse_enum_labels
 99   nil
100 end
drop_enum(enum, opts=OPTS) click to toggle source

Run the SQL to drop the enum type with the given name. Options:

:if_exists

Do not raise an error if the enum type does not exist

:cascade

Also drop other objects that depend on the enum type

    # File lib/sequel/extensions/pg_enum.rb
115 def drop_enum(enum, opts=OPTS)
116   sql = "DROP TYPE#{' IF EXISTS' if opts[:if_exists]} #{quote_schema_table(enum)}#{' CASCADE' if opts[:cascade]}"
117   run sql
118   parse_enum_labels
119   nil
120 end
rename_enum(enum, new_name) click to toggle source

Run the SQL to rename the enum type with the given name to the another given name.

    # File lib/sequel/extensions/pg_enum.rb
104 def rename_enum(enum, new_name)
105   sql = "ALTER TYPE #{quote_schema_table(enum)} RENAME TO #{quote_schema_table(new_name)}"
106   run sql
107   parse_enum_labels
108   nil
109 end

Private Instance Methods

parse_enum_labels() click to toggle source

Parse the pg_enum table to get enum values, and the pg_type table to get names and array oids for enums.

    # File lib/sequel/extensions/pg_enum.rb
127 def parse_enum_labels
128   enum_labels = metadata_dataset.from(:pg_enum).
129     order(:enumtypid, :enumsortorder).
130     select_hash_groups(Sequel.cast(:enumtypid, Integer).as(:v), :enumlabel).freeze
131   enum_labels.each_value(&:freeze)
132 
133   if respond_to?(:register_array_type)
134     array_types = metadata_dataset.
135       from(:pg_type).
136       where(:oid=>enum_labels.keys).
137       exclude(:typarray=>0).
138       select_map([:typname, Sequel.cast(:typarray, Integer).as(:v)])
139 
140     existing_oids = conversion_procs.keys
141     array_types.each do |name, oid|
142       next if existing_oids.include?(oid)
143       register_array_type(name, :oid=>oid)
144     end
145   end
146 
147   Sequel.synchronize{@enum_labels.replace(enum_labels)}
148 end
schema_post_process(_) click to toggle source

For schema entries that are enums, set the type to :enum and add a :enum_values entry with the enum values.

Calls superclass method
    # File lib/sequel/extensions/pg_enum.rb
152 def schema_post_process(_)
153   super.each do |_, s|
154     oid = s[:oid]
155     if values = Sequel.synchronize{@enum_labels[oid]}
156       s[:type] = :enum
157       s[:enum_values] = values
158     end
159   end
160 end
typecast_value_enum(value) click to toggle source

Typecast the given value to a string.

    # File lib/sequel/extensions/pg_enum.rb
163 def typecast_value_enum(value)
164   value.to_s
165 end