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<chapter id="functions">

<title>Functions and Operators</title>

<tbody>

<row>

<entry><literal><function>ascii</function>(<type>text</type>)</literal></entry>

<entry><literal><function>ascii</function>(<type>string</type>)</literal></entry>

<entry><type>int</type></entry>

<entry><acronym>ASCII</acronym> code of the first byte of the argument</entry>

<entry><literal>ascii('x')</literal></entry>

<row>

<entry>

<literal><function>convert</function>(<parameter>string</parameter>

<type>text</type>,

<literal><function>convert</function>(<parameter>string</parameter> <type>text</type>,

<optional><parameter>src_encoding</parameter> <type>name</type>,</optional>

<parameter>dest_encoding</parameter> <type>name</type>)</literal>

</entry>

</row>

<row>

<entry><literal><function>initcap</function>(<type>text</type>)</literal></entry>

<entry><literal><function>initcap</function>(<type>string</type>)</literal></entry>

<entry><type>text</type></entry>

<entry>

Convert the first letter of each word to uppercase and the

</row>

<row>

<entry><literal><function>length</function>(<parameter>string</parameter> <type>text</type>)</literal></entry>

<entry><literal><function>length</function>(<parameter>string</parameter>)</literal></entry>

<entry><type>int</type></entry>

<entry>

Number of characters in <parameter>string</parameter>

</row>

<row>

<entry><literal><function>md5</function>(<parameter>string</parameter> <type>text</type>)</literal></entry>

<entry><literal><function>md5</function>(<parameter>string</parameter>)</literal></entry>

<entry><type>text</type></entry>

<entry>

Calculates the MD5 hash of <parameter>string</parameter>,

</row>

<row>

<entry><literal><function>quote_ident</function>(<parameter>string</parameter> text)</literal></entry>

<entry><literal><function>quote_ident</function>(<parameter>string</parameter>)</literal></entry>

<entry><type>text</type></entry>

<entry>

Return the given string suitably quoted to be used as an identifier

</row>

<row>

<entry><literal><function>quote_literal</function>(<parameter>string</parameter> text)</literal></entry>

<entry><literal><function>quote_literal</function>(<parameter>string</parameter>)</literal></entry>

<entry><type>text</type></entry>

<entry>

Return the given string suitably quoted to be used as a string literal

</row>

<row>

<entry><literal><function>to_ascii</function>(<type>text</type>

<optional>, <parameter>encoding</parameter></optional>)</literal></entry>

<entry><literal><function>to_ascii</function>(<parameter>string</parameter> <type>text</type>

<optional>, <parameter>encoding</parameter> <type>text</type></optional>)</literal></entry>

<entry><type>text</type></entry>

<entry>

Convert <parameter>text</parameter> to <acronym>ASCII</acronym> from another encoding

Convert <parameter>string</parameter> to <acronym>ASCII</acronym> from another encoding

<footnote>

<para>

The <function>to_ascii</function> function supports conversion from

<row>

<entry>

<literal><function>translate</function>(<parameter>string</parameter>

<type>text</type>,

<literal><function>translate</function>(<parameter>string</parameter> <type>text</type>,

<parameter>from</parameter> <type>text</type>,

<parameter>to</parameter> <type>text</type>)</literal>

</entry>