Help Center/ GaussDB(DWS)/ SQL Syntax Reference/ SQL Syntax Reference (9.1.0.x)/ Functions and Operators/ Range Functions and Operators/ Range Functions
Updated on 2024-09-02 GMT+08:00
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Range Functions

lower(anyrange)

Description: Lower bound of range

Return type: Range's element type

Example:

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SELECT lower(numrange(1.1,2.2)) AS RESULT;
 result 
--------
    1.1
(1 row)

upper(anyrange)

Description: Upper bound of range

Return type: Range's element type

Example:

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SELECT upper(numrange(1.1,2.2)) AS RESULT;
 result 
--------
    2.2
(1 row)

isempty(anyrange)

Description: Is the range empty?

Return type: boolean

Example:

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SELECT isempty(numrange(1.1,2.2)) AS RESULT;
 result 
--------
 f
(1 row)

lower_inc(anyrange)

Description: Is the lower bound inclusive?

Return type: boolean

Example:

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SELECT lower_inc(numrange(1.1,2.2)) AS RESULT;
 result 
--------
 t
(1 row)

upper_inc(anyrange)

Description: Is the upper bound inclusive?

Return type: boolean

Example:

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SELECT upper_inc(numrange(1.1,2.2)) AS RESULT;
 result 
--------
 f
(1 row)

lower_inf(anyrange)

Description: Is the lower bound infinite?

Return type: boolean

Example:

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SELECT lower_inf('(,)'::daterange) AS RESULT;
 result 
--------
 t
(1 row)

upper_inf(anyrange)

Description: Is the upper bound infinite?

Return type: boolean

Example:

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SELECT upper_inf('(,)'::daterange) AS RESULT;
 result 
--------
 t
(1 row)

The lower and upper functions return null if the range is empty or the requested bound is infinite. The lower_inc, upper_inc, lower_inf, and upper_inf functions all return false for an empty range.