diff options
Diffstat (limited to 'doc/src/sgml/ref/create_language.sgml')
| -rw-r--r-- | doc/src/sgml/ref/create_language.sgml | 125 |
1 files changed, 57 insertions, 68 deletions
diff --git a/doc/src/sgml/ref/create_language.sgml b/doc/src/sgml/ref/create_language.sgml index b35d8b7c92..73e409c42a 100644 --- a/doc/src/sgml/ref/create_language.sgml +++ b/doc/src/sgml/ref/create_language.sgml @@ -15,29 +15,22 @@ <REFSYNOPSISDIV> <REFSYNOPSISDIVINFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSYNOPSISDIVINFO> <SYNOPSIS> - CREATE [TRUSTED] PROCEDURAL LANGUAGE '<replaceable class="parameter">langname</replaceable>' - HANDLER <replaceable class="parameter">call_handler</replaceable> - LANCOMPILER '<replaceable class="parameter">comment</replaceable>' +CREATE [ TRUSTED ] PROCEDURAL LANGUAGE '<replaceable class="parameter">langname</replaceable>' + HANDLER <replaceable class="parameter">call_handler</replaceable> + LANCOMPILER '<replaceable class="parameter">comment</replaceable>' </SYNOPSIS> <REFSECT2 ID="R2-SQL-CREATELANGUAGE-1"> <REFSECT2INFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSECT2INFO> <TITLE> Inputs </TITLE> <PARA> - </PARA> - <VARIABLELIST> - <VARLISTENTRY> - <TERM> - </TERM> - <LISTITEM> - <PARA> <VARIABLELIST> <VARLISTENTRY> <TERM> @@ -99,14 +92,12 @@ </LISTITEM> </VARLISTENTRY> </variablelist> - </LISTITEM> - </VARLISTENTRY> - </VARIABLELIST> + </REFSECT2> <REFSECT2 ID="R2-SQL-CREATELANGUAGE-2"> <REFSECT2INFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSECT2INFO> <TITLE> Outputs @@ -116,6 +107,7 @@ <VARIABLELIST> <VARLISTENTRY> <TERM> +<replaceable>status</replaceable> </TERM> <LISTITEM> <PARA> @@ -152,22 +144,25 @@ <REFSECT1 ID="R1-SQL-CREATELANGUAGE-1"> <REFSECT1INFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSECT1INFO> <TITLE> Description </TITLE> <PARA> - Using <command>CREATE LANGUAGE</command>, a PostgreSQL user can register - a new language with PostgreSQL. Subsequently, functions and + Using <command>CREATE LANGUAGE</command>, a +<productname>Postgres</productname> user can register + a new language with <productname>Postgres</productname>. +Subsequently, functions and trigger procedures can be defined in this new language. - The user must have the PostgreSQL superuser privilege to + The user must have the <productname>Postgres</productname> + superuser privilege to register a new language. </PARA> <REFSECT2 ID="R2-SQL-CREATELANGUAGE-3"> <REFSECT2INFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSECT2INFO> <TITLE> Writing PL handlers @@ -175,9 +170,9 @@ <PARA> The call handler for a procedural language must be written in a compiler language such as 'C' and registered with - PostgreSQL as a function taking no arguments and returning - opaque type. - <comment>What does `opaque type' mean?</comment> + <productname>Postgres</productname> as a function taking + no arguments and returning the + <type>opaque</type> type, a placeholder for unspecified or undefined types.. This prevents the call handler from being called directly as a function from queries. </para> @@ -214,11 +209,11 @@ It's up to the call handler to fetch the <filename>pg_proc</filename> entry and to analyze the argument and return types of the called - procedure. The <function>AS</function> clause from the + procedure. The AS clause from the <command>CREATE FUNCTION</command> of the procedure will be found in the <literal>prosrc</literal> attribute of the - <filename>pg_proc</filename> entry. This may be the + <filename>pg_proc</filename> table entry. This may be the source text in the procedural language itself (like for PL/Tcl), a pathname to a file or anything else that tells the call handler what to @@ -227,43 +222,40 @@ <REFSECT2 ID="R2-SQL-CREATELANGUAGE-4"> <REFSECT2INFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSECT2INFO> <TITLE> Notes </TITLE> <PARA> - Use <citerefentry> - <refentrytitle>CREATE FUNCTION</refentrytitle> - </citerefentry> + Use <command>CREATE FUNCTION</command> to create a function. </para> <para> - Use <citerefentry> - <refentrytitle>DROP LANGUAGE</refentrytitle> - </citerefentry> to drop procedural languages. + Use <command>DROP LANGUAGE</command> to drop procedural languages. </para> <para> Refer to the table <filename>pg_language</filename> for further information: - <programlisting> - <computeroutput> - Table = pg_language - +--------------------------+--------------------------+-------+ - | Field | Type | Length| - +--------------------------+--------------------------+-------+ - | lanname | name | 32 | - | lancompiler | text | var | - +--------------------------+--------------------------+-------+ +<programlisting> +<computeroutput> +Table = pg_language ++--------------------------+--------------------------+-------+ +| Field | Type | Length| ++--------------------------+--------------------------+-------+ +| lanname | name | 32 | +| lancompiler | text | var | ++--------------------------+--------------------------+-------+ + +lanname |lancompiler +--------+-------------- +internal|n/a +lisp |/usr/ucb/liszt +C |/bin/cc +sql |postgres +</computeroutput> +</programlisting> - lanname |lancompiler - --------+-------------- - internal|n/a - lisp |/usr/ucb/liszt - C |/bin/cc - sql |postgres - </computeroutput> - </programlisting> </para> </refsect2> </refsect1> @@ -274,11 +266,9 @@ </TITLE> <PARA> Since the call handler for a procedural language must be - registered with PostgreSQL in the 'C' language, it inherits - all the restrictions of 'C' functions. - <comment> - What are these restrictions? - </comment> + registered with <productname>Postgres</productname> in the 'C' language, + it inherits + all the capabilities and restrictions of 'C' functions. </para> </refsect1> <REFSECT1 ID="R1-SQL-CREATELANGUAGE-5"> @@ -340,22 +330,21 @@ </ProgramListing> <para> Only a few thousand lines of code have to be added instead - of the dots to complete the PL call handler. See <citerefentry> - <refentrytitle>CREATE FUNCTION</refentrytitle> - </citerefentry> for information on how to compile + of the dots to complete the PL call handler. +See <command>CREATE FUNCTION</command> for information on how to compile it into a loadable module .</para> <para> The following commands then register the sample procedural - language.</para> + language: <programlisting> - CREATE FUNCTION plsample_call_handler () RETURNS opaque - AS '/usr/local/pgsql/lib/plsample.so' - LANGUAGE 'C'; +CREATE FUNCTION plsample_call_handler () RETURNS opaque + AS '/usr/local/pgsql/lib/plsample.so' + LANGUAGE 'C'; - CREATE PROCEDURAL LANGUAGE 'plsample' - HANDLER plsample_call_handler - LANCOMPILER 'PL/Sample'; +CREATE PROCEDURAL LANGUAGE 'plsample' + HANDLER plsample_call_handler + LANCOMPILER 'PL/Sample'; </programlisting> </REFSECT1> @@ -364,18 +353,18 @@ Compatibility </TITLE> <PARA> - CREATE LANGUAGE is a PostgreSQL extension. + CREATE LANGUAGE is a <productname>Postgres</productname> extension. </PARA> <REFSECT2 ID="R2-SQL-CREATELANGUAGE-5"> <REFSECT2INFO> - <DATE>1998-04-15</DATE> + <DATE>1998-09-09</DATE> </REFSECT2INFO> <TITLE> SQL92 </TITLE> <PARA> - There is no CREATE LANGUAGE statement in SQL92. + There is no <command>CREATE LANGUAGE</command> statement in SQL92. </PARA> </refsect2> </refsect1> |