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Reorder VARCHAR() to appear before CHAR() in docs.
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Bruce Momjian
parent
d14c64c4a3
commit
0eed62f34d
@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.110 2002/12/06 05:17:42 momjian Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.111 2003/01/15 18:01:04 momjian Exp $
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-->
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<chapter id="datatype">
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@ -86,18 +86,18 @@ $Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.110 2002/12/06 05:17:42 m
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<entry>binary data</entry>
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</row>
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<row>
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<entry><type>character(<replaceable>n</replaceable>)</type></entry>
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<entry><type>char(<replaceable>n</replaceable>)</type></entry>
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<entry>fixed-length character string</entry>
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</row>
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<row>
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<entry><type>character varying(<replaceable>n</replaceable>)</type></entry>
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<entry><type>varchar(<replaceable>n</replaceable>)</type></entry>
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<entry>variable-length character string</entry>
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</row>
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<row>
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<entry><type>character(<replaceable>n</replaceable>)</type></entry>
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<entry><type>char(<replaceable>n</replaceable>)</type></entry>
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<entry>fixed-length character string</entry>
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</row>
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<row>
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<entry><type>cidr</type></entry>
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<entry></entry>
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@ -248,7 +248,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.110 2002/12/06 05:17:42 m
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The following types (or spellings thereof) are specified by
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<acronym>SQL</acronym>: <type>bit</type>, <type>bit
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varying</type>, <type>boolean</type>, <type>char</type>,
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<type>character</type>, <type>character varying</type>,
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<type>character varying</type>, <type>character</type>,
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<type>varchar</type>, <type>date</type>, <type>double
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precision</type>, <type>integer</type>, <type>interval</type>,
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<type>numeric</type>, <type>decimal</type>, <type>real</type>,
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@ -811,14 +811,14 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (
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</row>
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</thead>
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<tbody>
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<row>
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<entry><type>character(<replaceable>n</>)</type>, <type>char(<replaceable>n</>)</type></entry>
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<entry>fixed-length, blank padded</entry>
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</row>
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<row>
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<entry><type>character varying(<replaceable>n</>)</type>, <type>varchar(<replaceable>n</>)</type></entry>
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<entry>variable-length with limit</entry>
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</row>
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<row>
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<entry><type>character(<replaceable>n</>)</type>, <type>char(<replaceable>n</>)</type></entry>
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<entry>fixed-length, blank padded</entry>
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</row>
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<row>
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<entry><type>text</type></entry>
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<entry>variable unlimited length</entry>
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@ -835,29 +835,29 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (
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<para>
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<acronym>SQL</acronym> defines two primary character types:
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<type>character(<replaceable>n</>)</type> and <type>character
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varying(<replaceable>n</>)</type>, where <replaceable>n</> is a
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positive integer. Both of these types can store strings up to
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<type>character varying(<replaceable>n</>)</type> and
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<type>character(<replaceable>n</>)</type>, where <replaceable>n</>
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is a positive integer. Both of these types can store strings up to
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<replaceable>n</> characters in length. An attempt to store a
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longer string into a column of these types will result in an
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error, unless the excess characters are all spaces, in which case
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the string will be truncated to the maximum length. (This
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somewhat bizarre exception is required by the
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<acronym>SQL</acronym> standard.) If the string to be stored is
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shorter than the declared length, values of type
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<type>character</type> will be space-padded; values of type
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<type>character varying</type> will simply store the shorter
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the string will be truncated to the maximum length. (This somewhat
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bizarre exception is required by the <acronym>SQL</acronym>
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standard.) If the string to be stored is shorter than the declared
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length, values of type <type>character</type> will be space-padded;
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values of type <type>character varying</type> will simply store the
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shorter
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string.
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</para>
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<note>
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<para>
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If one explicitly casts a value to
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<type>character(<replaceable>n</>)</type> or <type>character
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varying(<replaceable>n</>)</type>, then an overlength value will
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be truncated to <replaceable>n</> characters without raising an
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error. (This too is required by the <acronym>SQL</acronym>
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standard.)
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If one explicitly casts a value to <type>character
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varying(<replaceable>n</>)</type> or
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<type>character(<replaceable>n</>)</type>, then an over-length
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value will be truncated to <replaceable>n</> characters without
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raising an error. (This too is required by the
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<acronym>SQL</acronym> standard.)
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</para>
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</note>
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@ -870,14 +870,14 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (
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</note>
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<para>
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The notations <type>char(<replaceable>n</>)</type> and
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<type>varchar(<replaceable>n</>)</type> are aliases for
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<type>character(<replaceable>n</>)</type> and <type>character
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varying(<replaceable>n</>)</type>,
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respectively. <type>character</type> without length specifier is
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equivalent to <type>character(1)</type>; if <type>character
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varying</type> is used without length specifier, the type accepts
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strings of any size. The latter is a <productname>PostgreSQL</> extension.
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The notations <type>varchar(<replaceable>n</>)</type> and
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<type>char(<replaceable>n</>)</type> are aliases for <type>character
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varying(<replaceable>n</>)</type> and
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<type>character(<replaceable>n</>)</type>, respectively.
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<type>character</type> without length specifier is equivalent to
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<type>character(1)</type>; if <type>character varying</type> is used
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without length specifier, the type accepts strings of any size. The
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latter is a <productname>PostgreSQL</> extension.
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</para>
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<para>
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@ -961,19 +961,18 @@ SELECT b, char_length(b) FROM test2;
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<para>
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There are two other fixed-length character types in
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<productname>PostgreSQL</productname>, shown in <xref linkend="datatype-character-special-table">.
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The <type>name</type> type
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exists <emphasis>only</emphasis> for storage of internal catalog
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names and is not intended for use by the general user. Its length
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is currently defined as 64 bytes (63 usable characters plus terminator)
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but should be referenced using the constant
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<symbol>NAMEDATALEN</symbol>. The length is set at compile time
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(and is therefore adjustable for special uses); the default
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maximum length may change in a future release. The type
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<type>"char"</type> (note the quotes) is different from
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<type>char(1)</type> in that it only uses one byte of storage. It
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is internally used in the system catalogs as a poor-man's
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enumeration type.
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<productname>PostgreSQL</productname>, shown in <xref
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linkend="datatype-character-special-table">. The <type>name</type>
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type exists <emphasis>only</emphasis> for storage of internal
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catalog names and is not intended for use by the general user. Its
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length is currently defined as 64 bytes (63 usable characters plus
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terminator) but should be referenced using the constant
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<symbol>NAMEDATALEN</symbol>. The length is set at compile time (and
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is therefore adjustable for special uses); the default maximum
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length may change in a future release. The type <type>"char"</type>
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(note the quotes) is different from <type>char(1)</type> in that it
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only uses one byte of storage. It is internally used in the system
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catalogs as a poor-man's enumeration type.
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</para>
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<table id="datatype-character-special-table">
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@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.27 2002/08/28 14:35:36 momjian Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.28 2003/01/15 18:01:05 momjian Exp $
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-->
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<chapter id="sql">
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@ -1749,19 +1749,20 @@ CREATE TABLE SELLS
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<listitem>
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<para>
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CHAR(<replaceable class="parameter">n</replaceable>):
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fixed length character string of length
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VARCHAR(<replaceable class="parameter">n</replaceable>):
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varying length character string of maximum length
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<replaceable class="parameter">n</replaceable>.
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</para>
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</listitem>
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<listitem>
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<para>
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VARCHAR(<replaceable class="parameter">n</replaceable>):
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varying length character string of maximum length
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CHAR(<replaceable class="parameter">n</replaceable>):
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fixed length character string of length
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<replaceable class="parameter">n</replaceable>.
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</para>
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</listitem>
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</itemizedlist>
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</para>
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</sect3>
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