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
1016 def initialize(expr, path, opts=OPTS)
1017   @returning = opts[:returning]
1018   @on_empty = opts[:on_empty]
1019   super
1020 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
1071 def default_literal_append(ds, sql, v)
1072   if sql.respond_to?(:skip_auto_param)
1073     sql.skip_auto_param do
1074       ds.literal_append(sql, v)
1075     end
1076   else
1077     ds.literal_append(sql, v)
1078   end
1079 end

on_sql_value(value) click to toggle source

     # File lib/sequel/extensions/pg_json_ops.rb
1081 def on_sql_value(value)
1082   ON_SQL[value]
1083 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
1041 def to_s_append_args_passing(ds, sql)
1042   super
1043 
1044   if @returning
1045     sql << ' RETURNING ' << ds.db.cast_type_literal(@returning).to_s
1046   end
1047 end

to_s_append_function_name(ds, sql) click to toggle source

     # File lib/sequel/extensions/pg_json_ops.rb
1036 def to_s_append_function_name(ds, sql)
1037   sql << 'json_value('
1038 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
1050 def to_s_append_on_error(ds, sql)
1051   unless @on_empty.nil?
1052     sql << " "
1053     to_s_append_on_value(ds, sql, @on_empty)
1054     sql << " ON EMPTY"
1055   end
1056 
1057   super
1058 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
1061 def to_s_append_on_value(ds, sql, value)
1062   if v = on_sql_value(value)
1063     sql << v
1064   else
1065     sql << 'DEFAULT '
1066     default_literal_append(ds, sql, value)
1067   end
1068 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
1025 def transform_opts(transformer, opts)
1026   super
1027   opts[:returning] = @returning
1028   on_error = @on_error
1029   on_error = transformer.call(on_error) unless on_sql_value(on_error)
1030   opts[:on_error] = on_error
1031   on_empty = @on_empty
1032   on_empty = transformer.call(on_empty) unless on_sql_value(on_empty)
1033   opts[:on_empty] = on_empty
1034 end