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Add more appropriate markup.

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This commit is contained in:
Peter Eisentraut
2002-09-21 18:32:54 +00:00
parent 7233aae50b
commit bc49968764
77 changed files with 1481 additions and 1347 deletions
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32
doc/src/sgml/pltcl.sgml
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@@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.21 2002/08/22 00:01:40 tgl Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.22 2002/09/21 18:32:53 petere Exp $
-->
<chapter id="pltcl">
@@ -50,22 +50,22 @@ $Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.21 2002/08/22 00:01:40 tgl E
<para>
Sometimes it is desirable to write Tcl functions that are not restricted
to safe Tcl --- for example, one might want a Tcl function that sends
mail. To handle these cases, there is a variant of PL/Tcl called PL/TclU
mail. To handle these cases, there is a variant of <application>PL/Tcl</> called <literal>PL/TclU</>
(for untrusted Tcl). This is the exact same language except that a full
Tcl interpreter is used. <emphasis>If PL/TclU is used, it must be
Tcl interpreter is used. <emphasis>If <application>PL/TclU</> is used, it must be
installed as an untrusted procedural language</emphasis> so that only
database superusers can create functions in it. The writer of a PL/TclU
database superusers can create functions in it. The writer of a <application>PL/TclU</>
function must take care that the function cannot be used to do anything
unwanted, since it will be able to do anything that could be done by
a user logged in as the database administrator.
</para>
<para>
The shared object for the PL/Tcl and PL/TclU call handlers is
The shared object for the <application>PL/Tcl</> and <application>PL/TclU</> call handlers is
automatically built and installed in the
<productname>PostgreSQL</productname>
library directory if Tcl/Tk support is specified
in the configuration step of the installation procedure. To install
PL/Tcl and/or PL/TclU in a particular database, use the
<application>PL/Tcl</> and/or <application>PL/TclU</> in a particular database, use the
<filename>createlang</filename> script, for example
<literal>createlang pltcl <replaceable>dbname</></literal> or
<literal>createlang pltclu <replaceable>dbname</></literal>.
@@ -81,7 +81,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.21 2002/08/22 00:01:40 tgl E
<title>PL/Tcl Functions and Arguments</title>
<para>
To create a function in the PL/Tcl language, use the standard syntax
To create a function in the <application>PL/Tcl</> language, use the standard syntax
<programlisting>
CREATE FUNCTION <replaceable>funcname</replaceable> (<replaceable>argument-types</replaceable>) RETURNS <replaceable>return-type</replaceable> AS '
@@ -89,8 +89,8 @@ CREATE FUNCTION <replaceable>funcname</replaceable> (<replaceable>argument-types
' LANGUAGE 'pltcl';
</programlisting>
PL/TclU is the same, except that the language should be specified as
<literal>'pltclu'</>.
<application>PL/TclU</> is the same, except that the language should be specified as
<literal>pltclu</>.
</para>
<para>
@@ -197,7 +197,7 @@ CREATE FUNCTION overpaid_2 (EMP) RETURNS bool AS '
all PL/Tcl procedures executed in one backend share the same
safe Tcl interpreter. So, any global Tcl variable is accessible to
all PL/Tcl procedure calls, and will persist for the duration of the
SQL client connection. (Note that PL/TclU functions likewise share
SQL client connection. (Note that <application>PL/TclU</> functions likewise share
global data, but they are in a different Tcl interpreter and cannot
communicate with PL/Tcl functions.)
</para>
@@ -248,7 +248,7 @@ CREATE FUNCTION overpaid_2 (EMP) RETURNS bool AS '
setting up the query as a cursor and then saying <literal>FETCH n</>.
</para>
<para>
If the query is a SELECT statement, the values of the SELECT's
If the query is a <literal>SELECT</> statement, the values of the statement's
result columns are placed into Tcl variables named after the columns.
If the <literal>-array</> option is given, the column values are
instead stored into the named associative array, with the SELECT
@@ -267,7 +267,7 @@ spi_exec "SELECT count(*) AS cnt FROM pg_proc"
</programlisting>
will set the Tcl variable <literal>$cnt</> to the number of rows in
the pg_proc system catalog.
the <structname>pg_proc</> system catalog.
</para>
<para>
If the optional <replaceable>loop-body</> argument is given, it is
@@ -337,7 +337,7 @@ spi_exec -array C "SELECT * FROM pg_class" {
<para>
The optional value for <literal>-nulls</> is a string of spaces and
<literal>'n'</> characters telling <function>spi_execp</function>
which of the arguments are NULLs. If given, it must have exactly the
which of the arguments are null values. If given, it must have exactly the
same length as the <replaceable>value-list</replaceable>. If it
is not given, all the argument values are non-NULL.
</para>
@@ -504,7 +504,7 @@ SELECT 'doesn''t' AS ret
<listitem>
<para>
A Tcl list of the table field names, prefixed with an empty list
element. So looking up an element name in the list with Tcl's
element. So looking up an element name in the list with <application>Tcl</>'s
<function>lsearch</> command returns the element's number starting
with 1 for the first column, the same way the fields are customarily
numbered in <productname>PostgreSQL</productname>.
@@ -639,7 +639,7 @@ CREATE TRIGGER trig_mytab_modcount BEFORE INSERT OR UPDATE ON mytab
While the <literal>unknown</> module could actually contain any
initialization script you need, it normally defines a Tcl
<quote>unknown</> procedure that is invoked whenever Tcl does
not recognize an invoked procedure name. PL/Tcl's standard version
not recognize an invoked procedure name. <application>PL/Tcl</>'s standard version
of this procedure tries to find a module in <literal>pltcl_modules</>
that will define the required procedure. If one is found, it is
loaded into the interpreter, and then execution is allowed to
@@ -674,7 +674,7 @@ CREATE TRIGGER trig_mytab_modcount BEFORE INSERT OR UPDATE ON mytab
differ. Tcl, however, requires all procedure names to be distinct.
PL/Tcl deals with this by making the internal Tcl procedure names contain
the object
ID of the procedure's pg_proc row as part of their name. Thus,
ID of the procedure's <structname>pg_proc</> row as part of their name. Thus,
<productname>PostgreSQL</productname> functions with the same name
and different argument types will be different Tcl procedures too. This
is not normally a concern for a PL/Tcl programmer, but it might be visible