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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Range Functions and Operators</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="Functions and Operators" HREF="functions.html"><LINK REL="PREVIOUS" TITLE="Array Functions and Operators" HREF="functions-array.html"><LINK REL="NEXT" TITLE="Aggregate Functions" HREF="functions-aggregate.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="SECT1" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="Array Functions and Operators" HREF="functions-array.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="functions.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" >Chapter 9. Functions and Operators</TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="Aggregate Functions" HREF="functions-aggregate.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><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 ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="functions-array.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="functions-aggregate.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Array Functions and Operators</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="functions.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Aggregate Functions</TD ></TR ></TABLE ></DIV ></BODY ></HTML >