Difference between revisions of "CAST()"
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==Purpose== | ==Purpose== | ||
Function to convert the data type of an expression | Function to convert the data type of an expression | ||
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==Syntax== | ==Syntax== | ||
CAST(<exp> AS <expC>[(<expN1>[, <expN2>])] [NULL | NOT NULL]) | CAST(<exp> AS <expC>[(<expN1>[, <expN2>])] [NULL | NOT NULL]) | ||
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==See Also== | ==See Also== | ||
[[DTOC()]], [[DTOS()]], [[ETOS()]], [[LTOS()]], [[MTOS()]], [[STR()]] | [[DTOC()]], [[DTOS()]], [[ETOS()]], [[LTOS()]], [[MTOS()]], [[STR()]] | ||
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==Description== | ==Description== | ||
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====Data Type Abbreviations==== | ====Data Type Abbreviations==== | ||
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!Abbreviations||Data Type||Width Required||Precision Required | !Abbreviations||Data Type||Width Required||Precision Required | ||
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|D||DATE||No||No | |D||DATE||No||No | ||
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| − | |F||FLOAT||Yes||No, defaults to 0 | + | |valign="top"|F||valign="top"|FLOAT||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
| − | |G||LONG VARBINARY/GENERAL||No||No | + | |valign="top"|G||LONG VARBINARY/GENERAL||valign="top"|No||valign="top"|No |
|- | |- | ||
| − | |I, Int||INTEGER||Yes||No, defaults to 0 | + | |valign="top"|I, Int||INTEGER||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
|L||LOGICAL/BIT||No||No | |L||LOGICAL/BIT||No||No | ||
|- | |- | ||
| − | |M||LONG VARCHAR/MEMO||No||No | + | |valign="top"|M||LONG VARCHAR/MEMO||valign="top"|No||valign="top"|No |
|- | |- | ||
| − | |N, Num||NUMERIC||Yes||No, defaults to 0 | + | |valign="top"|N, Num||valign="top"|NUMERIC||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
| − | |P||PACKED DECIMAL||Yes||No, defaults to 0 | + | |valign="top"|P||valign="top"|PACKED DECIMAL||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
| − | |Q||QUAD||Yes||No, defaults to 0 | + | |valign="top"|Q||valign="top"|QUAD||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
| − | |R||REAL||Yes||No, defaults to 0 | + | |valign="top"|R||valign="top"|REAL||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
| − | |S||SHORT||Yes||No, defaults to 0 | + | |valign="top"|S||valign="top"|SHORT||valgn="top"|Yes||No, defaults to 0 |
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|T||DATETIME||No||No | |T||DATETIME||No||No | ||
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|Y||CURRENCY||No||No | |Y||CURRENCY||No||No | ||
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| − | |Z||ZONED||Yes||No, defaults to 0 | + | |valign="top"|Z||valign="top"|ZONED||valign="top"|Yes||No, defaults to 0 |
|- | |- | ||
|} | |} | ||
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If the specified width, <expN1> is less than that of <exp>, the result will be truncated. If greater, the result will be padded. Precision may be lost if the precision specified in <expN2> is less than that of <exp>. | If the specified width, <expN1> is less than that of <exp>, the result will be truncated. If greater, the result will be padded. Precision may be lost if the precision specified in <expN2> is less than that of <exp>. | ||
The optional NULL | NOT NULL determines whether null values are permitted or not. | The optional NULL | NOT NULL determines whether null values are permitted or not. | ||
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==Example== | ==Example== | ||
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</code> | </code> | ||
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[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:Functions]] | [[Category:Functions]] | ||
| + | [[Category:Formatting Functions]] | ||
[[Category:SQL]] | [[Category:SQL]] | ||
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Latest revision as of 07:57, 4 February 2013
Purpose
Function to convert the data type of an expression
Syntax
CAST(<exp> AS <expC>[(<expN1>[, <expN2>])] [NULL | NOT NULL])
See Also
DTOC(), DTOS(), ETOS(), LTOS(), MTOS(), STR()
Description
The CAST() function converts the expression in <exp> to the data type specified in <expC> and returns the result. The <expC> can be the full data type name, e.g. Character or supported abbreviation, e.g. C or Char. For data types requiring width and precision information, these are specified in <expN1> and <expN2> respectively.
Data Type Abbreviations
| Abbreviations | Data Type | Width Required | Precision Required |
|---|---|---|---|
| B | TINYINT/DOUBLE | No | No |
| C, Char | CHARACTER | Yes | No |
| D | DATE | No | No |
| F | FLOAT | Yes | No, defaults to 0 |
| G | LONG VARBINARY/GENERAL | No | No |
| I, Int | INTEGER | Yes | No, defaults to 0 |
| L | LOGICAL/BIT | No | No |
| M | LONG VARCHAR/MEMO | No | No |
| N, Num | NUMERIC | Yes | No, defaults to 0 |
| P | PACKED DECIMAL | Yes | No, defaults to 0 |
| Q | QUAD | Yes | No, defaults to 0 |
| R | REAL | Yes | No, defaults to 0 |
| S | SHORT | Yes | No, defaults to 0 |
| T | DATETIME | No | No |
| V | VAXDATE | No | No |
| Y | CURRENCY | No | No |
| Z | ZONED | Yes | No, defaults to 0 |
If the specified width, <expN1> is less than that of <exp>, the result will be truncated. If greater, the result will be padded. Precision may be lost if the precision specified in <expN2> is less than that of <exp>.
The optional NULL | NOT NULL determines whether null values are permitted or not.
Example
> m_var = "date" > ? cast("12/12/2005" as (m_var)) 12/12/2005 > open database southwind > select cast(limit-balance as numeric(10,2)) from example
