Class Sequel::Postgres::JSONBaseOp
In: lib/sequel/extensions/pg_json_ops.rb
Parent: Sequel::SQL::Wrapper

The JSONBaseOp class is a simple container for a single object that defines methods that yield Sequel expression objects representing PostgreSQL json operators and functions.

In the method documentation examples, assume that:

  json_op = Sequel.pg_json(:json)

Methods

Constants

GET = ["(".freeze, " -> ".freeze, ")".freeze].freeze
GET_TEXT = ["(".freeze, " ->> ".freeze, ")".freeze].freeze
GET_PATH = ["(".freeze, " #> ".freeze, ")".freeze].freeze
GET_PATH_TEXT = ["(".freeze, " #>> ".freeze, ")".freeze].freeze

Public Instance methods

Get JSON array element or object field as json. If an array is given, gets the object at the specified path.

  json_op[1] # (json -> 1)
  json_op['a'] # (json -> 'a')
  json_op[%w'a b'] # (json #> ARRAY['a', 'b'])

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 110
110:       def [](key)
111:         if is_array?(key)
112:           json_op(GET_PATH, wrap_array(key))
113:         else
114:           json_op(GET, key)
115:         end
116:       end

Returns a set of json values for the elements in the json array.

  json_op.array_elements # json_array_elements(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 122
122:       def array_elements
123:         function(:array_elements)
124:       end

Returns a set of text values for the elements in the json array.

  json_op.array_elements_text # json_array_elements_text(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 129
129:       def array_elements_text
130:         function(:array_elements_text)
131:       end

Get the length of the outermost json array.

  json_op.array_length # json_array_length(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 136
136:       def array_length
137:         Sequel::SQL::NumericExpression.new(:NOOP, function(:array_length))
138:       end

Returns a set of key and value pairs, where the keys are text and the values are JSON.

  json_op.each # json_each(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 144
144:       def each
145:         function(:each)
146:       end

Returns a set of key and value pairs, where the keys and values are both text.

  json_op.each_text # json_each_text(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 152
152:       def each_text
153:         function(:each_text)
154:       end

Returns a json value for the object at the given path.

  json_op.extract('a') # json_extract_path(json, 'a')
  json_op.extract('a', 'b') # json_extract_path(json, 'a', 'b')

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 160
160:       def extract(*a)
161:         self.class.new(function(:extract_path, *a))
162:       end

Returns a text value for the object at the given path.

  json_op.extract_text('a') # json_extract_path_text(json, 'a')
  json_op.extract_text('a', 'b') # json_extract_path_text(json, 'a', 'b')

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 168
168:       def extract_text(*a)
169:         Sequel::SQL::StringExpression.new(:NOOP, function(:extract_path_text, *a))
170:       end
get(key)

Alias for #[]

Get JSON array element or object field as text. If an array is given, gets the object at the specified path.

  json_op.get_text(1) # (json ->> 1)
  json_op.get_text('a') # (json ->> 'a')
  json_op.get_text(%w'a b') # (json #>> ARRAY['a', 'b'])

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 178
178:       def get_text(key)
179:         if is_array?(key)
180:           json_op(GET_PATH_TEXT, wrap_array(key))
181:         else
182:           json_op(GET_TEXT, key)
183:         end
184:       end

Returns a set of keys AS text in the json object.

  json_op.keys # json_object_keys(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 189
189:       def keys
190:         function(:object_keys)
191:       end

Expands the given argument using the columns in the json.

  json_op.populate(arg) # json_populate_record(arg, json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 196
196:       def populate(arg)
197:         SQL::Function.new(function_name(:populate_record), arg, self)
198:       end

Expands the given argument using the columns in the json.

  json_op.populate_set(arg) # json_populate_recordset(arg, json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 203
203:       def populate_set(arg)
204:         SQL::Function.new(function_name(:populate_recordset), arg, self)
205:       end

Returns a json value stripped of all internal null values.

  json_op.strip_nulls # json_strip_nulls(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 210
210:       def strip_nulls
211:         self.class.new(function(:strip_nulls))
212:       end

Builds arbitrary record from json object. You need to define the structure of the record using as on the resulting object:

  json_op.to_record.as(:x, [Sequel.lit('a integer'), Sequel.lit('b text')]) # json_to_record(json) AS x(a integer, b text)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 218
218:       def to_record
219:         function(:to_record)
220:       end

Builds arbitrary set of records from json array of objects. You need to define the structure of the records using as on the resulting object:

  json_op.to_recordset.as(:x, [Sequel.lit('a integer'), Sequel.lit('b text')]) # json_to_recordset(json) AS x(a integer, b text)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 226
226:       def to_recordset
227:         function(:to_recordset)
228:       end

Returns the type of the outermost json value as text.

  json_op.typeof # json_typeof(json)

[Source]

     # File lib/sequel/extensions/pg_json_ops.rb, line 233
233:       def typeof
234:         function(:typeof)
235:       end

[Validate]