A binary literal is a sequence of hexadecimal characters consisting of digits 0-9 and uppercase and lowercase letters A-F. When you enter binary data as literals, you must precede the data by 0x (a zero, followed by an x), and there should be an even number of digits to the right of this prefix. For example, the hexadecimal equivalent of 39 is 0027, and is expressed as 0x0027.

Hexadecimal constants in the form of 0x12345678 are treated as binary strings. An unlimited number of digits can be added after the 0x.

A binary literal is sometimes referred to as a binary constant. In SQL Anywhere, the preferred term is binary literal.

You can use the CAST, CONVERT, HEXTOINT, and INTTOHEX functions to convert a binary string to an integer. The CAST and CONVERT functions convert hexadecimal constants to TINYINT, signed and unsigned 32-bit integer, signed and unsigned 64-bit integer, NUMERIC, and so on. The HEXTOINT function only converts a hexadecimal constant to a signed 32-bit-integer.

The value returned by the CAST function cannot exceed 8 digits. Values exceeding 8 digits return an error. Zeroes are added to the left of values less than 8 digits. For example, the following argument returns the value -2,147,483,647:

SELECT CAST ( 0x0080000001 AS INT ); |

The following argument returns an error because the 10-digit value cannot be represented as a signed 32-bit integer:

SELECT CAST ( 0xff80000001 AS INT ); |

The value returned by the HEXTOINT function can exceed 8 digits if the value can be represented as a signed 32-bit integer. The HEXTOINT function accepts string literals or variables consisting only of digits and the uppercase or lowercase letters A-F, with or without a 0x prefix. The hexadecimal value represents a negative integer when the 8th digit from the right is one of the digits 8-9, the uppercase or lowercase letters A-F, or the previous leading digits are all uppercase or lowercase letter F.

The following arguments return the value -2,147,483,647:

SELECT HEXTOINT( '0xFF80000001' ); |

SELECT HEXTOINT( '0x80000001' ); |

SELECT HEXTOINT ( '0xFFFFFFFFFFFFFFFF80000001' ); |

The following argument returns an error because the argument represents a positive integer value that cannot be represented as a signed 32-bit integer:

SELECT HEXTOINT( '0x0080000001' ); |

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