2013-07-04 03:25:22 +04:00
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A memorandum for HRR
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======================
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Type Casts
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-----------
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### PostgreSQL
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http://www.postgresql.org/docs/9.2/static/sql-expressions.html#SQL-SYNTAX-TYPE-CASTS
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> A type cast specifies a conversion from one data type to another.
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> PostgreSQL accepts two equivalent syntaxes for type casts:
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>
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> CAST ( <expression> AS <type> )
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> <expression>::<type>
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>
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> The CAST syntax conforms to SQL; the syntax with :: is historical PostgreSQL usage.
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### SQL Server 2012
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http://msdn.microsoft.com/en-US/library/ms187928(v=sql.110).aspx
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> Syntax for CAST:
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>
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> CAST ( <expression> AS <data_type> [ ( <length> ) ] )
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### SQLite3
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http://www.sqlite.org/syntaxdiagrams.html#expr
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> expr: (excerption)
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>
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> CAST ( <expr> AS <type-name> )
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>
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> type-name:
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>
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> <name> [ ...n ] [ ( <signed-number> ) | ( <signed-number> , <signed-number> ) ]
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