class Sequel::Postgres::JSONValueOp

Object representing json_value calls

Constants

ON_SQL

Attributes

on_empty[R]

How to handle cases where the JSON path expression evaluation yields an empty set.

returning[R]

The database type to cast returned values to

Public Class Methods

new(expr, path, opts=OPTS) click to toggle source

See JSONBaseOp#value for documentation of the options.

Calls superclass method Sequel::Postgres::JSONExistsOp::new

     # File lib/sequel/extensions/pg_json_ops.rb
1023 def initialize(expr, path, opts=OPTS)
1024   @returning = opts[:returning]
1025   @on_empty = opts[:on_empty]
1026   super
1027 end

Private Instance Methods

default_literal_append(ds, sql, v) click to toggle source

Do not auto paramterize default value, as PostgreSQL doesn't allow it.

     # File lib/sequel/extensions/pg_json_ops.rb
1078 def default_literal_append(ds, sql, v)
1079   if sql.respond_to?(:skip_auto_param)
1080     sql.skip_auto_param do
1081       ds.literal_append(sql, v)
1082     end
1083   else
1084     ds.literal_append(sql, v)
1085   end
1086 end

on_sql_value(value) click to toggle source

     # File lib/sequel/extensions/pg_json_ops.rb
1088 def on_sql_value(value)
1089   ON_SQL[value]
1090 end

to_s_append_args_passing(ds, sql) click to toggle source

Also append the optional RETURNING fragment

Calls superclass method Sequel::Postgres::JSONExistsOp#to_s_append_args_passing

     # File lib/sequel/extensions/pg_json_ops.rb
1048 def to_s_append_args_passing(ds, sql)
1049   super
1050 
1051   if @returning
1052     sql << ' RETURNING ' << ds.db.cast_type_literal(@returning).to_s
1053   end
1054 end

to_s_append_function_name(ds, sql) click to toggle source

     # File lib/sequel/extensions/pg_json_ops.rb
1043 def to_s_append_function_name(ds, sql)
1044   sql << 'json_value('
1045 end

to_s_append_on_error(ds, sql) click to toggle source

Also append the optional ON EMPTY fragment

Calls superclass method Sequel::Postgres::JSONExistsOp#to_s_append_on_error

     # File lib/sequel/extensions/pg_json_ops.rb
1057 def to_s_append_on_error(ds, sql)
1058   unless @on_empty.nil?
1059     sql << " "
1060     to_s_append_on_value(ds, sql, @on_empty)
1061     sql << " ON EMPTY"
1062   end
1063 
1064   super
1065 end

to_s_append_on_value(ds, sql, value) click to toggle source

Handle DEFAULT values in ON EMPTY/ON ERROR fragments

     # File lib/sequel/extensions/pg_json_ops.rb
1068 def to_s_append_on_value(ds, sql, value)
1069   if v = on_sql_value(value)
1070     sql << v
1071   else
1072     sql << 'DEFAULT '
1073     default_literal_append(ds, sql, value)
1074   end
1075 end

transform_opts(transformer, opts) click to toggle source

Also handle transforming the returning and on_empty options.

Calls superclass method Sequel::Postgres::JSONExistsOp#transform_opts

     # File lib/sequel/extensions/pg_json_ops.rb
1032 def transform_opts(transformer, opts)
1033   super
1034   opts[:returning] = @returning
1035   on_error = @on_error
1036   on_error = transformer.call(on_error) unless on_sql_value(on_error)
1037   opts[:on_error] = on_error
1038   on_empty = @on_empty
1039   on_empty = transformer.call(on_empty) unless on_sql_value(on_empty)
1040   opts[:on_empty] = on_empty
1041 end