diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/src/sgml/release.sgml | 4 | ||||
| -rw-r--r-- | doc/src/sgml/syntax.sgml | 37 |
2 files changed, 22 insertions, 19 deletions
diff --git a/doc/src/sgml/release.sgml b/doc/src/sgml/release.sgml index 382029b81ff..cc03ae9cbe3 100644 --- a/doc/src/sgml/release.sgml +++ b/doc/src/sgml/release.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.193 2003/06/17 23:12:36 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.194 2003/06/19 23:22:40 tgl Exp $ --> <appendix id="release"> @@ -24,6 +24,8 @@ CDATA means the content is "SGML-free", so you can write without worries about funny characters. --> <literallayout><![CDATA[ +Dollar sign ($) is no longer allowed in operator names +Dollar sign ($) can be a non-first character in identifiers Precision in FLOAT(p) is now interpreted as bits, not decimal digits Functional indexes have been generalized into expressional indexes CHAR(n) to TEXT conversion automatically strips trailing blanks diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml index a1c0767e4cc..372aca2ca71 100644 --- a/doc/src/sgml/syntax.sgml +++ b/doc/src/sgml/syntax.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.78 2003/06/06 15:04:01 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.79 2003/06/19 23:22:40 tgl Exp $ --> <chapter id="sql-syntax"> @@ -109,10 +109,15 @@ INSERT INTO MY_TABLE VALUES (3, 'hi there'); (<literal>a</literal>-<literal>z</literal>, but also letters with diacritical marks and non-Latin letters) or an underscore (<literal>_</literal>). Subsequent characters in an identifier or - key word can be letters, digits - (<literal>0</literal>-<literal>9</literal>), or underscores, - although the SQL standard will not define a key word that contains - digits or starts or ends with an underscore. + key word can be letters, underscores, digits + (<literal>0</literal>-<literal>9</literal>), or dollar signs + (<literal>$</>). Note that dollar signs are not allowed in identifiers + according to the letter of the SQL standard, so their use may render + applications less portable. + The SQL standard will not define a key word that contains + digits or starts or ends with an underscore, so identifiers of this + form are safe against possible conflict with future extensions of the + standard. </para> <para> @@ -478,20 +483,13 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> ) An operator is a sequence of up to <symbol>NAMEDATALEN</symbol>-1 (63 by default) characters from the following list: <literallayout> -+ - * / < > = ~ ! @ # % ^ & | ` ? $ ++ - * / < > = ~ ! @ # % ^ & | ` ? </literallayout> There are a few restrictions on operator names, however: <itemizedlist> <listitem> <para> - <literal>$</> (dollar) cannot be a single-character operator, although it - can be part of a multiple-character operator name. - </para> - </listitem> - - <listitem> - <para> <literal>--</literal> and <literal>/*</literal> cannot appear anywhere in an operator name, since they will be taken as the start of a comment. @@ -503,7 +501,7 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> ) A multiple-character operator name cannot end in <literal>+</> or <literal>-</>, unless the name also contains at least one of these characters: <literallayout> -~ ! @ # % ^ & | ` ? $ +~ ! @ # % ^ & | ` ? </literallayout> For example, <literal>@-</literal> is an allowed operator name, but <literal>*-</literal> is not. This restriction allows @@ -539,9 +537,9 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> ) <listitem> <para> A dollar sign (<literal>$</literal>) followed by digits is used - to represent the positional parameters in the body of a function + to represent a positional parameter in the body of a function definition or a prepared statement. In other contexts the - dollar sign may be part of an operator name. + dollar sign may be part of an identifier. </para> </listitem> @@ -965,9 +963,12 @@ SELECT 3 OPERATOR(pg_catalog.+) 4; <title>Positional Parameters</title> <para> - A positional parameter reference is used to indicate a parameter + A positional parameter reference is used to indicate a value that is supplied externally to an SQL statement. Parameters are - used in SQL function definitions and in prepared queries. + used in SQL function definitions and in prepared queries. Some + client libraries also support specifying data values separately + from the SQL command string, in which case parameters are used to + refer to the out-of-line data values. The form of a parameter reference is: <synopsis> $<replaceable>number</replaceable> |