diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml index 3ca2d7f296b54937ba910bc60bf2146c78431a33..21fa569a0162fe1df56bd53e0bc61d93f2f1b4ad 100644 --- a/doc/src/sgml/datatype.sgml +++ b/doc/src/sgml/datatype.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.56 2001/06/18 19:05:11 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.57 2001/08/07 22:41:49 petere Exp $ --> <chapter id="datatype"> @@ -552,28 +552,24 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl <table tocentry="1"> <title>Character Types</title> - <tgroup cols="3"> + <tgroup cols="2"> <thead> <row> - <entry>Type Name</entry> - <entry>Storage</entry> + <entry>Type name</entry> <entry>Description</entry> </row> </thead> <tbody> <row> - <entry>character(n), char(n)</entry> - <entry>(4+n) bytes</entry> + <entry>character(<replaceable>n</>), char(<replaceable>n</>)</entry> <entry>Fixed-length blank padded</entry> </row> <row> - <entry>character varying(n), varchar(n)</entry> - <entry>(4+n) bytes</entry> + <entry>character varying(<replaceable>n</>), varchar(<replaceable>n</>)</entry> <entry>Variable-length with limit</entry> </row> <row> <entry>text</entry> - <entry>(4+n) bytes</entry> <entry>Variable unlimited length</entry> </row> </tbody> @@ -624,9 +620,15 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl </para> <para> - Refer to <xref linkend="sql-syntax-strings"> for information about - the syntax of string literals, and to <xref linkend="functions"> - for information about available operators and functions. + The storage requirement for data of these types is 4 bytes plus + the actual string, and in case of <type>character</type> plus the + padding. Long strings will actually be compressed by the system + automatically. In any case, the longest possible character string + that can be stored is about 1 GB. (The maximum value that will be + allowed for <replaceable>n</> in the data type declaration is + actually larger than that. It wouldn't be very useful to change + this because with multi-byte character encodings the number of + characters and bytes can be quite different anyway.) </para> <tip> @@ -637,6 +639,12 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl </para> </tip> + <para> + Refer to <xref linkend="sql-syntax-strings"> for information about + the syntax of string literals, and to <xref linkend="functions"> + for information about available operators and functions. + </para> + <example> <title>Using the character types</title>