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2.5 KiB
2.5 KiB
slug | sidebar_position | sidebar_label |
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/en/sql-reference/table-functions/format | 65 | format |
format
Parses data from arguments according to specified input format. If structure argument is not specified, it's extracted from the data.
Syntax
format(format_name, [structure], data)
Parameters
format_name
— The format of the data.structure
- Structure of the table. Optional. Format 'column1_name column1_type, column2_name column2_type, ...'.data
— String literal or constant expression that returns a string containing data in specified format
Returned value
A table with data parsed from data
argument according to specified format and specified or extracted structure.
Examples
Without structure
argument:
Query:
SELECT * FROM format(JSONEachRow,
$$
{"a": "Hello", "b": 111}
{"a": "World", "b": 123}
{"a": "Hello", "b": 112}
{"a": "World", "b": 124}
$$)
Result:
┌───b─┬─a─────┐
│ 111 │ Hello │
│ 123 │ World │
│ 112 │ Hello │
│ 124 │ World │
└─────┴───────┘
Query:
DESC format(JSONEachRow,
$$
{"a": "Hello", "b": 111}
{"a": "World", "b": 123}
{"a": "Hello", "b": 112}
{"a": "World", "b": 124}
$$)
Result:
┌─name─┬─type──────────────┬─default_type─┬─default_expression─┬─comment─┬─codec_expression─┬─ttl_expression─┐
│ b │ Nullable(Float64) │ │ │ │ │ │
│ a │ Nullable(String) │ │ │ │ │ │
└──────┴───────────────────┴──────────────┴────────────────────┴─────────┴──────────────────┴────────────────┘
With structure
argument:
Query:
SELECT * FROM format(JSONEachRow, 'a String, b UInt32',
$$
{"a": "Hello", "b": 111}
{"a": "World", "b": 123}
{"a": "Hello", "b": 112}
{"a": "World", "b": 124}
$$)
Result:
┌─a─────┬───b─┐
│ Hello │ 111 │
│ World │ 123 │
│ Hello │ 112 │
│ World │ 124 │
└───────┴─────┘
See Also