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><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="FUNCTIONS-RANGE"
>9.19. Range Functions and Operators</A
></H1
><P
> See <A
HREF="rangetypes.html"
>Section 8.17</A
> for an overview of range types.
</P
><P
> <A
HREF="functions-range.html#RANGE-OPERATORS-TABLE"
>Table 9-44</A
> shows the operators
available for range types.
</P
><DIV
CLASS="TABLE"
><A
NAME="RANGE-OPERATORS-TABLE"
></A
><P
><B
>Table 9-44. Range Operators</B
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><COL><COL><COL><COL><THEAD
><TR
><TH
>Operator</TH
><TH
>Description</TH
><TH
>Example</TH
><TH
>Result</TH
></TR
></THEAD
><TBODY
><TR
><TD
> <TT
CLASS="LITERAL"
>=</TT
> </TD
><TD
>equal</TD
><TD
><TT
CLASS="LITERAL"
>int4range(1,5) = '[1,4]'::int4range</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
><></TT
> </TD
><TD
>not equal</TD
><TD
><TT
CLASS="LITERAL"
>numrange(1.1,2.2) <> numrange(1.1,2.3)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
><</TT
> </TD
><TD
>less than</TD
><TD
><TT
CLASS="LITERAL"
>int4range(1,10) < int4range(2,3)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>></TT
> </TD
><TD
>greater than</TD
><TD
><TT
CLASS="LITERAL"
>int4range(1,10) > int4range(1,5)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
><=</TT
> </TD
><TD
>less than or equal</TD
><TD
><TT
CLASS="LITERAL"
>numrange(1.1,2.2) <= numrange(1.1,2.2)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>>=</TT
> </TD
><TD
>greater than or equal</TD
><TD
><TT
CLASS="LITERAL"
>numrange(1.1,2.2) >= numrange(1.1,2.0)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>@></TT
> </TD
><TD
>contains range</TD
><TD
><TT
CLASS="LITERAL"
>int4range(2,4) @> int4range(2,3)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>@></TT
> </TD
><TD
>contains element</TD
><TD
><TT
CLASS="LITERAL"
>'[2011-01-01,2011-03-01)'::tsrange @> '2011-01-10'::timestamp</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
><@</TT
> </TD
><TD
>range is contained by</TD
><TD
><TT
CLASS="LITERAL"
>int4range(2,4) <@ int4range(1,7)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
><@</TT
> </TD
><TD
>element is contained by</TD
><TD
><TT
CLASS="LITERAL"
>42 <@ int4range(1,7)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>f</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>&&</TT
> </TD
><TD
>overlap (have points in common)</TD
><TD
><TT
CLASS="LITERAL"
>int8range(3,7) && int8range(4,12)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
><<</TT
> </TD
><TD
>strictly left of</TD
><TD
><TT
CLASS="LITERAL"
>int8range(1,10) << int8range(100,110)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>>></TT
> </TD
><TD
>strictly right of</TD
><TD
><TT
CLASS="LITERAL"
>int8range(50,60) >> int8range(20,30)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>&<</TT
> </TD
><TD
>does not extend to the right of</TD
><TD
><TT
CLASS="LITERAL"
>int8range(1,20) &< int8range(18,20)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>&></TT
> </TD
><TD
>does not extend to the left of</TD
><TD
><TT
CLASS="LITERAL"
>int8range(7,20) &> int8range(5,10)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>-|-</TT
> </TD
><TD
>is adjacent to</TD
><TD
><TT
CLASS="LITERAL"
>numrange(1.1,2.2) -|- numrange(2.2,3.3)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>t</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>+</TT
> </TD
><TD
>union</TD
><TD
><TT
CLASS="LITERAL"
>numrange(5,15) + numrange(10,20)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>[5,20)</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>*</TT
> </TD
><TD
>intersection</TD
><TD
><TT
CLASS="LITERAL"
>int8range(5,15) * int8range(10,20)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>[10,15)</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
>-</TT
> </TD
><TD
>difference</TD
><TD
><TT
CLASS="LITERAL"
>int8range(5,15) - int8range(10,20)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>[5,10)</TT
></TD
></TR
></TBODY
></TABLE
></DIV
><P
> The simple comparison operators <TT
CLASS="LITERAL"
><</TT
>,
<TT
CLASS="LITERAL"
>></TT
>, <TT
CLASS="LITERAL"
><=</TT
>, and
<TT
CLASS="LITERAL"
>>=</TT
> compare the lower bounds first, and only if those
are equal, compare the upper bounds. These comparisons are not usually
very useful for ranges, but are provided to allow B-tree indexes to be
constructed on ranges.
</P
><P
> The left-of/right-of/adjacent operators always return false when an empty
range is involved; that is, an empty range is not considered to be either
before or after any other range.
</P
><P
> The union and difference operators will fail if the resulting range would
need to contain two disjoint sub-ranges, as such a range cannot be
represented.
</P
><P
> <A
HREF="functions-range.html#RANGE-FUNCTIONS-TABLE"
>Table 9-45</A
> shows the functions
available for use with range types.
</P
><DIV
CLASS="TABLE"
><A
NAME="RANGE-FUNCTIONS-TABLE"
></A
><P
><B
>Table 9-45. Range Functions</B
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><COL><COL><COL><COL><COL><THEAD
><TR
><TH
>Function</TH
><TH
>Return Type</TH
><TH
>Description</TH
><TH
>Example</TH
><TH
>Result</TH
></TR
></THEAD
><TBODY
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>lower</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
>range's element type</TD
><TD
>lower bound of range</TD
><TD
><TT
CLASS="LITERAL"
>lower(numrange(1.1,2.2))</TT
></TD
><TD
><TT
CLASS="LITERAL"
>1.1</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>upper</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
>range's element type</TD
><TD
>upper bound of range</TD
><TD
><TT
CLASS="LITERAL"
>upper(numrange(1.1,2.2))</TT
></TD
><TD
><TT
CLASS="LITERAL"
>2.2</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>isempty</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
><TT
CLASS="TYPE"
>boolean</TT
></TD
><TD
>is the range empty?</TD
><TD
><TT
CLASS="LITERAL"
>isempty(numrange(1.1,2.2))</TT
></TD
><TD
><TT
CLASS="LITERAL"
>false</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>lower_inc</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
><TT
CLASS="TYPE"
>boolean</TT
></TD
><TD
>is the lower bound inclusive?</TD
><TD
><TT
CLASS="LITERAL"
>lower_inc(numrange(1.1,2.2))</TT
></TD
><TD
><TT
CLASS="LITERAL"
>true</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>upper_inc</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
><TT
CLASS="TYPE"
>boolean</TT
></TD
><TD
>is the upper bound inclusive?</TD
><TD
><TT
CLASS="LITERAL"
>upper_inc(numrange(1.1,2.2))</TT
></TD
><TD
><TT
CLASS="LITERAL"
>false</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>lower_inf</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
><TT
CLASS="TYPE"
>boolean</TT
></TD
><TD
>is the lower bound infinite?</TD
><TD
><TT
CLASS="LITERAL"
>lower_inf('(,)'::daterange)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>true</TT
></TD
></TR
><TR
><TD
> <TT
CLASS="LITERAL"
> <CODE
CLASS="FUNCTION"
>upper_inf</CODE
>(<TT
CLASS="TYPE"
>anyrange</TT
>)
</TT
>
</TD
><TD
><TT
CLASS="TYPE"
>boolean</TT
></TD
><TD
>is the upper bound infinite?</TD
><TD
><TT
CLASS="LITERAL"
>upper_inf('(,)'::daterange)</TT
></TD
><TD
><TT
CLASS="LITERAL"
>true</TT
></TD
></TR
></TBODY
></TABLE
></DIV
><P
> The <CODE
CLASS="FUNCTION"
>lower</CODE
> and <CODE
CLASS="FUNCTION"
>upper</CODE
> functions return null
if the range is empty or the requested bound is infinite.
The <CODE
CLASS="FUNCTION"
>lower_inc</CODE
>, <CODE
CLASS="FUNCTION"
>upper_inc</CODE
>,
<CODE
CLASS="FUNCTION"
>lower_inf</CODE
>, and <CODE
CLASS="FUNCTION"
>upper_inf</CODE
>
functions all return false for an empty range.
</P
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