database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-30 11:03:19 +03:00
Code Activity

Allow psql's \df and \do commands to specify argument types.

Browse Source 
When dealing with overloaded function or operator names, having
to look through a long list of matches is tedious.  Let's extend
these commands to allow specification of (input) argument types
to let such results be trimmed down.  Each additional argument
is treated the same as the pattern argument of \dT and matched
against the appropriate argument's type name.

While at it, fix \dT (and these new options) to recognize the
usual notation of "foo[]" for "the array type over foo", and
to handle the special abbreviations allowed by the backend
grammar, such as "int" for "integer".

Greg Sabino Mullane, revised rather significantly by me

Discussion: https://postgr.es/m/CAKAnmmLF9Hhu02N+s7uAyLc5J1xZReg72HQUoiKhNiJV3_jACQ@mail.gmail.com
This commit is contained in:
Tom Lane
2021-04-07 23:02:16 -04:00
parent f57a2f5e03
commit a3027e1e7f
8 changed files with 374 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files

40
doc/src/sgml/ref/psql-ref.sgml
View File

@ -1567,7 +1567,7 @@ testdb=>
<varlistentry>
<term><literal>\df[anptwS+] [ <link linkend="app-psql-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
<term><literal>\df[anptwS+] [ <link linkend="app-psql-patterns"><replaceable class="parameter">pattern</replaceable></link> [ <replaceable class="parameter">arg_pattern</replaceable> ... ] ]</literal></term>
<listitem>
<para>
@ -1580,6 +1580,11 @@ testdb=&gt;
If <replaceable
class="parameter">pattern</replaceable> is specified, only
functions whose names match the pattern are shown.
Any additional arguments are type-name patterns, which are matched
to the type names of the first, second, and so on arguments of the
function. (Matching functions can have more arguments than what
you specify. To prevent that, write a dash <literal>-</literal> as
the last <replaceable class="parameter">arg_pattern</replaceable>.)
By default, only user-created
objects are shown; supply a pattern or the <literal>S</literal>
modifier to include system objects.
@ -1589,14 +1594,6 @@ testdb=&gt;
language, source code and description.
</para>
<tip>
<para>
To look up functions taking arguments or returning values of a specific
data type, use your pager's search capability to scroll through the
<literal>\df</literal> output.
</para>
</tip>
</listitem>
</varlistentry>
@ -1721,12 +1718,19 @@ testdb=&gt;
<varlistentry>
<term><literal>\do[S+] [ <link linkend="app-psql-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
<term><literal>\do[S+] [ <link linkend="app-psql-patterns"><replaceable class="parameter">pattern</replaceable></link> [ <replaceable class="parameter">arg_pattern</replaceable> [ <replaceable class="parameter">arg_pattern</replaceable> ] ] ]</literal></term>
<listitem>
<para>
Lists operators with their operand and result types.
If <replaceable class="parameter">pattern</replaceable> is
specified, only operators whose names match the pattern are listed.
If one <replaceable class="parameter">arg_pattern</replaceable> is
specified, only prefix operators whose right argument's type name
matches that pattern are listed.
If two <replaceable class="parameter">arg_pattern</replaceable>s
are specified, only binary operators whose argument type names match
those patterns are listed. (Alternatively, write <literal>-</literal>
for the unused argument of a unary operator.)
By default, only user-created objects are shown; supply a
pattern or the <literal>S</literal> modifier to include system
objects.
@ -4986,6 +4990,22 @@ second | four
</programlisting>
</para>
<para>
Here is an example of using the <command>\df</command> command to
find only functions with names matching <literal>int*pl</literal>
and whose second argument is of type <type>bigint</type>:
<programlisting>
testdb=&gt; <userinput>\df int*pl * bigint</userinput>
List of functions
Schema | Name | Result data type | Argument data types | Type
------------+---------+------------------+---------------------+------
pg_catalog | int28pl | bigint | smallint, bigint | func
pg_catalog | int48pl | bigint | integer, bigint | func
pg_catalog | int8pl | bigint | bigint, bigint | func
(3 rows)
</programlisting>
</para>
<para>
When suitable, query results can be shown in a crosstab representation
with the <command>\crosstabview</command> command: