11<!--
2- $Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.56 2001/06/18 19:05:11 tgl Exp $
2+ $Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.57 2001/08/07 22:41:49 petere Exp $
33-->
44
55 <chapter id="datatype">
@@ -552,28 +552,24 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl
552552
553553 <table tocentry="1">
554554 <title>Character Types</title>
555- <tgroup cols="3 ">
555+ <tgroup cols="2 ">
556556 <thead>
557557 <row>
558- <entry>Type Name</entry>
559- <entry>Storage</entry>
558+ <entry>Type name</entry>
560559<entry>Description</entry>
561560 </row>
562561 </thead>
563562 <tbody>
564563 <row>
565- <entry>character(n), char(n)</entry>
566- <entry>(4+n) bytes</entry>
564+ <entry>character(<replaceable>n</>), char(<replaceable>n</>)</entry>
567565<entry>Fixed-length blank padded</entry>
568566 </row>
569567 <row>
570- <entry>character varying(n), varchar(n)</entry>
571- <entry>(4+n) bytes</entry>
568+ <entry>character varying(<replaceable>n</>), varchar(<replaceable>n</>)</entry>
572569<entry>Variable-length with limit</entry>
573570 </row>
574571 <row>
575572<entry>text</entry>
576- <entry>(4+n) bytes</entry>
577573<entry>Variable unlimited length</entry>
578574 </row>
579575 </tbody>
@@ -624,9 +620,15 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl
624620 </para>
625621
626622 <para>
627- Refer to <xref linkend="sql-syntax-strings"> for information about
628- the syntax of string literals, and to <xref linkend="functions">
629- for information about available operators and functions.
623+ The storage requirement for data of these types is 4 bytes plus
624+ the actual string, and in case of <type>character</type> plus the
625+ padding. Long strings will actually be compressed by the system
626+ automatically. In any case, the longest possible character string
627+ that can be stored is about 1 GB. (The maximum value that will be
628+ allowed for <replaceable>n</> in the data type declaration is
629+ actually larger than that. It wouldn't be very useful to change
630+ this because with multi-byte character encodings the number of
631+ characters and bytes can be quite different anyway.)
630632 </para>
631633
632634 <tip>
@@ -637,6 +639,12 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl
637639 </para>
638640 </tip>
639641
642+ <para>
643+ Refer to <xref linkend="sql-syntax-strings"> for information about
644+ the syntax of string literals, and to <xref linkend="functions">
645+ for information about available operators and functions.
646+ </para>
647+
640648 <example>
641649 <title>Using the character types</title>
642650