Data representation in JSON format

Bool

Boolean value.

• Type in JSON: bool.
• Sample YDB value: true.
• Sample JSON value: true.

Int8, Int16, Int32, Int64

Signed integer types.

• Type in JSON: number.
• Sample YDB value: 123456, -123456.
• Sample JSON value: 123456, -123456.

Uint8, Uint16, Uint32, Uint64

Unsigned integer types.

• Type in JSON: number.
• Sample YDB value: 123456.
• Sample JSON value: 123456.

Float

Real 4-byte number.

• Type in JSON: number.
• Sample YDB value: 0.12345679.
• Sample JSON value: 0.12345679.

Double

Real 8-byte number.

• Type in JSON: number.
• Sample YDB value: 0.12345678901234568.
• Sample JSON value: 0.12345678901234568.

Decimal

Fixed-precision number. Only Decimal(22, 9) is supported.

• Type in JSON: string.
• Sample YDB value: -320.789.
• Sample JSON value: "-320.789".

String, Yson

Binary strings. Encoding algorithm depending on the byte value:

• [0-31] — \u00XX (6 characters denoting the Unicode character code).
• [32-126] — as is. These are readable single-byte characters that don't need to be escaped.
• [127-255] — \u00XX.

Decoding is a reverse process. Character codes in \u00XX, maximum 255.

• Type in JSON: string.

• Sample YDB value: A sequence of 4 bytes:

  • 5 0x05: A control character.
  • 10 0x0a: The \n newline character.
  • 107 0x6b: The k character.
  • 255 0xff: The ÿ character in Unicode.

• Sample JSON value: "\u0005\nk\u00FF".

Utf8, Json, Uuid

String types in UTF-8. Such strings are represented in JSON as strings with JSON characters escaped: \\, \", \n, \r, \t, \f.

• Type in JSON: string.

• Sample YDB value: C++ code:

  "Escaped characters: "
  "\\ \" \f \b \t \r\n"
  "Non-escaped characters: "
  "/ ' < > & []() ".
  

• Sample JSON value: "Escaped characters: \\ \" \f \b \t \r\nNon-escaped characters: / ' < > & []() ".

Date

Date. Uint64, unix time days.

• Type in JSON: string.
• Sample YDB value: 18367.
• Sample JSON value: "2020-04-15".

Datetime

Date and time. Uint64, unix time seconds.

• Type in JSON: string.
• Sample YDB value: 1586966302.
• Sample JSON value: "2020-04-15T15:58:22Z".

Timestamp

Date and time. Uint64, unix time microseconds.

• Type in JSON: string.
• Sample YDB value: 1586966302504185.
• Sample JSON value: "2020-04-15T15:58:22.504185Z".

Interval

Time interval. Int64, precision to the microsecond, the interval values must not exceed 24 hours.

• Type in JSON: number.
• Sample YDB value: 123456, -123456.
• Sample JSON value: 123456, -123456.

Optional

Means that the value can be null. If the value is null, then in JSON it's also null. If the value is not null, then the JSON value is expressed as if the type isn't Optional.

• Type in JSON is missing.
• Sample YDB value: null.
• Sample JSON value: null.

List

List. An ordered set of values of a given type.

• Type in JSON: array.

• Sample YDB value:

  • Type: List<Int32>.
  • Value: 1, 10, 100.

• Sample JSON value: [1,10,100].

Stream

Stream. Single-pass iterator by same-type values,

• Type in JSON: array.

• Sample YDB value:

  • Type: Stream<Int32>.
  • Value: 1, 10, 100.

• Sample JSON value: [1,10,100].

Struct

Structure. An unordered set of values with the specified names and type.

• Type in JSON: object.

• Sample YDB value:

  • Type: Struct<'Id':Uint32,'Name':String,'Value':Int32,'Description':Utf8?>;
  • Value: "Id":1,"Name":"Anna","Value":-100,"Description":null.

• Sample JSON value: {"Id":1,"Name":"Anna","Value":-100,"Description":null}.

Tuple

Tuple. An ordered set of values of the set types.

• Type in JSON: array.

• Sample YDB value:

  • Type: Tuple<Int32??,Int64???,String??,Utf8???>;
  • Value: 10,-1,null,"Some string".

• Sample JSON value: [10,-1,null,"Some string"].

Dict

Dictionary. An unordered set of key-value pairs. The type is set both for the key and the value. It's written in JSON to an array of arrays including two items.

• Type in JSON: array.

• Sample YDB value:

  • Type: Dict<Int64,String>.
  • Value: 1:"Value1",2:"Value2".

• Sample JSON value: [[1,"Value1"],[2,"Value2"]].