BigQuery 字符串格式为 json

Question

Is the following a full list of all value types as they're passed to json in BigQuery? I've gotten this by trial and error but haven't been able to find this in the documentation:

select
    NULL as NullValue,
    FALSE as BoolValue,
    DATE '2014-01-01' as DateValue,
    INTERVAL 1 year as IntervalValue,
    DATETIME '2014-01-01 01:02:03' as DatetimeValue,
    TIMESTAMP '2014-01-01 01:02:03' as TimestampValue,
    "Hello" as StringValue,
    B"abc" as BytesValue,
    123 as IntegerValue,
    NUMERIC '3.14' as NumericValue,
    3.14 as FloatValue,
    TIME '12:30:00.45' as TimeValue,
    [1,2,3] as ArrayValue,
    STRUCT('Mark' as first, 'Thomas' as last) as StructValue,
    [STRUCT(1 as x, 2 as y), STRUCT(5 as x, 6 as y)] as ArrayStructValue,
    STRUCT(1 as x, [1,2,3] as y, ('a','b','c') as z) as StructNestedValue

{
  "NullValue": null,
  "BoolValue": "false", // why not just false without quotes?
  "DateValue": "2014-01-01",
  "IntervalValue": "1-0 0 0:0:0",
  "DatetimeValue": "2014-01-01T01:02:03",
  "TimestampValue": "2014-01-01T01:02:03Z",
  "StringValue": "Hello",
  "BytesValue": "YWJj",
  "IntegerValue": "123",
  "NumericValue": "3.14",
  "FloatValue": "3.14",
  "TimeValue": "12:30:00.450000",
  "ArrayValue": ["1", "2", "3"],
  "StructValue": {
    "first": "Mark",
    "last": "Thomas"
  },
  "ArrayStructValue": [
    {"x": "1", "y": "2"},
    {"x": "5", "y": "6"}
  ],
  "StructNestedValue": {
    "x": "1",
    "y": ["1", 2", "3"],
    "z": {"a": "a", b": "b", "c": "c"}
  }
}

Honestly, it seems to me that other than the null value and the array [] or struct {} container, everything is string-enclosed, which seems a bit odd.

Answer 1

According to this document , json is built on two structures:

A collection of name/value pairs. In various languages, this is realized as an object, record, struct, dictionary, hash table, keyed list, or associative array.

An ordered list of values. In most languages, this is realized as an array, vector, list, or sequence.

The result of the SELECT query is in json format, wherein [] depicts an array datatype, {} depicts an object datatype and double quotes(" ") depicts a string value as in the query itself.