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diff --git a/doc/src/sgml/html/functions-enum.html b/doc/src/sgml/html/functions-enum.html new file mode 100644 index 0000000..9aaf8ae --- /dev/null +++ b/doc/src/sgml/html/functions-enum.html @@ -0,0 +1,84 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>9.10. Enum Support Functions</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="functions-datetime.html" title="9.9. Date/Time Functions and Operators" /><link rel="next" href="functions-geometry.html" title="9.11. Geometric Functions and Operators" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">9.10. Enum Support Functions</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="functions-datetime.html" title="9.9. Date/Time Functions and Operators">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="functions.html" title="Chapter 9. Functions and Operators">Up</a></td><th width="60%" align="center">Chapter 9. Functions and Operators</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="functions-geometry.html" title="9.11. Geometric Functions and Operators">Next</a></td></tr></table><hr /></div><div class="sect1" id="FUNCTIONS-ENUM"><div class="titlepage"><div><div><h2 class="title" style="clear: both">9.10. Enum Support Functions</h2></div></div></div><p> + For enum types (described in <a class="xref" href="datatype-enum.html" title="8.7. Enumerated Types">Section 8.7</a>), + there are several functions that allow cleaner programming without + hard-coding particular values of an enum type. + These are listed in <a class="xref" href="functions-enum.html#FUNCTIONS-ENUM-TABLE" title="Table 9.35. Enum Support Functions">Table 9.35</a>. The examples + assume an enum type created as: + +</p><pre class="programlisting"> +CREATE TYPE rainbow AS ENUM ('red', 'orange', 'yellow', 'green', 'blue', 'purple'); +</pre><p> + + </p><div class="table" id="FUNCTIONS-ENUM-TABLE"><p class="title"><strong>Table 9.35. Enum Support Functions</strong></p><div class="table-contents"><table class="table" summary="Enum Support Functions" border="1"><colgroup><col /></colgroup><thead><tr><th class="func_table_entry"><p class="func_signature"> + Function + </p> + <p> + Description + </p> + <p> + Example(s) + </p></th></tr></thead><tbody><tr><td class="func_table_entry"><p class="func_signature"> + <a id="id-1.5.8.16.3.2.2.1.1.1.1" class="indexterm"></a> + <code class="function">enum_first</code> ( <code class="type">anyenum</code> ) + → <code class="returnvalue">anyenum</code> + </p> + <p> + Returns the first value of the input enum type. + </p> + <p> + <code class="literal">enum_first(null::rainbow)</code> + → <code class="returnvalue">red</code> + </p></td></tr><tr><td class="func_table_entry"><p class="func_signature"> + <a id="id-1.5.8.16.3.2.2.2.1.1.1" class="indexterm"></a> + <code class="function">enum_last</code> ( <code class="type">anyenum</code> ) + → <code class="returnvalue">anyenum</code> + </p> + <p> + Returns the last value of the input enum type. + </p> + <p> + <code class="literal">enum_last(null::rainbow)</code> + → <code class="returnvalue">purple</code> + </p></td></tr><tr><td class="func_table_entry"><p class="func_signature"> + <a id="id-1.5.8.16.3.2.2.3.1.1.1" class="indexterm"></a> + <code class="function">enum_range</code> ( <code class="type">anyenum</code> ) + → <code class="returnvalue">anyarray</code> + </p> + <p> + Returns all values of the input enum type in an ordered array. + </p> + <p> + <code class="literal">enum_range(null::rainbow)</code> + → <code class="returnvalue">{red,orange,yellow,green,blue,purple}</code> + </p></td></tr><tr><td class="func_table_entry"><p class="func_signature"> + <code class="function">enum_range</code> ( <code class="type">anyenum</code>, <code class="type">anyenum</code> ) + → <code class="returnvalue">anyarray</code> + </p> + <p> + Returns the range between the two given enum values, as an ordered + array. The values must be from the same enum type. If the first + parameter is null, the result will start with the first value of + the enum type. + If the second parameter is null, the result will end with the last + value of the enum type. + </p> + <p> + <code class="literal">enum_range('orange'::rainbow, 'green'::rainbow)</code> + → <code class="returnvalue">{orange,yellow,green}</code> + </p> + <p> + <code class="literal">enum_range(NULL, 'green'::rainbow)</code> + → <code class="returnvalue">{red,orange,yellow,green}</code> + </p> + <p> + <code class="literal">enum_range('orange'::rainbow, NULL)</code> + → <code class="returnvalue">{orange,yellow,green,blue,purple}</code> + </p></td></tr></tbody></table></div></div><br class="table-break" /><p> + Notice that except for the two-argument form of <code class="function">enum_range</code>, + these functions disregard the specific value passed to them; they care + only about its declared data type. Either null or a specific value of + the type can be passed, with the same result. It is more common to + apply these functions to a table column or function argument than to + a hardwired type name as used in the examples. + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="functions-datetime.html" title="9.9. Date/Time Functions and Operators">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="functions.html" title="Chapter 9. Functions and Operators">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="functions-geometry.html" title="9.11. Geometric Functions and Operators">Next</a></td></tr><tr><td width="40%" align="left" valign="top">9.9. Date/Time Functions and Operators </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 9.11. 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