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Rename TABLE() to ROWS FROM().

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SQL-standard TABLE() is a subset of UNNEST(); they deal with arrays and
other collection types.  This feature, however, deals with set-returning
functions.  Use a different syntax for this feature to keep open the
possibility of implementing the standard TABLE().
This commit is contained in:
Noah Misch
2013-12-10 09:34:37 -05:00
parent 01cc1fecfd
commit 53685d7981
11 changed files with 123 additions and 123 deletions
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16
doc/src/sgml/queries.sgml
View File

@ -647,7 +647,7 @@ FROM (VALUES ('anne', 'smith'), ('bob', 'jones'), ('joe', 'blow'))
</para>
<para>
Table functions may also be combined using the <literal>TABLE</literal>
Table functions may also be combined using the <literal>ROWS FROM</>
syntax, with the results returned in parallel columns; the number of
result rows in this case is that of the largest function result, with
smaller results padded with NULLs to match.
@ -655,7 +655,7 @@ FROM (VALUES ('anne', 'smith'), ('bob', 'jones'), ('joe', 'blow'))
<synopsis>
<replaceable>function_call</replaceable> <optional>WITH ORDINALITY</optional> <optional><optional>AS</optional> <replaceable>table_alias</replaceable> <optional>(<replaceable>column_alias</replaceable> <optional>, ... </optional>)</optional></optional>
TABLE( <replaceable>function_call</replaceable> <optional>, ... </optional> ) <optional>WITH ORDINALITY</optional> <optional><optional>AS</optional> <replaceable>table_alias</replaceable> <optional>(<replaceable>column_alias</replaceable> <optional>, ... </optional>)</optional></optional>
ROWS FROM( <replaceable>function_call</replaceable> <optional>, ... </optional> ) <optional>WITH ORDINALITY</optional> <optional><optional>AS</optional> <replaceable>table_alias</replaceable> <optional>(<replaceable>column_alias</replaceable> <optional>, ... </optional>)</optional></optional>
</synopsis>
<para>
@ -674,7 +674,7 @@ TABLE( <replaceable>function_call</replaceable> <optional>, ... </optional> ) <o
any number of array parameters, and it returns a corresponding number of
columns, as if <literal>UNNEST</literal>
(<xref linkend="functions-array">) had been called on each parameter
separately and combined using the <literal>TABLE</literal> construct.
separately and combined using the <literal>ROWS FROM</literal> construct.
</para>
<synopsis>
@ -683,7 +683,7 @@ UNNEST( <replaceable>array_expression</replaceable> <optional>, ... </optional>
<para>
If no <replaceable>table_alias</replaceable> is specified, the function
name is used as the table name; in the case of a <literal>TABLE()</>
name is used as the table name; in the case of a <literal>ROWS FROM()</>
construct, the first function's name is used.
</para>
@ -731,20 +731,20 @@ SELECT * FROM vw_getfoo;
<synopsis>
<replaceable>function_call</replaceable> <optional>AS</optional> <replaceable>alias</replaceable> (<replaceable>column_definition</replaceable> <optional>, ... </optional>)
<replaceable>function_call</replaceable> AS <optional><replaceable>alias</replaceable></optional> (<replaceable>column_definition</replaceable> <optional>, ... </optional>)
TABLE( ... <replaceable>function_call</replaceable> AS (<replaceable>column_definition</replaceable> <optional>, ... </optional>) <optional>, ... </optional> )
ROWS FROM( ... <replaceable>function_call</replaceable> AS (<replaceable>column_definition</replaceable> <optional>, ... </optional>) <optional>, ... </optional> )
</synopsis>
<para>
When not using the <literal>TABLE()</> syntax,
When not using the <literal>ROWS FROM()</> syntax,
the <replaceable>column_definition</replaceable> list replaces the column
alias list that could otherwise be attached to the <literal>FROM</>
item; the names in the column definitions serve as column aliases.
When using the <literal>TABLE()</> syntax,
When using the <literal>ROWS FROM()</> syntax,
a <replaceable>column_definition</replaceable> list can be attached to
each member function separately; or if there is only one member function
and no <literal>WITH ORDINALITY</> clause,
a <replaceable>column_definition</replaceable> list can be written in
place of a column alias list following <literal>TABLE()</>.
place of a column alias list following <literal>ROWS FROM()</>.
</para>
<para>

19
doc/src/sgml/ref/select.sgml
View File

@ -56,7 +56,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="parameter">expression</replac
[ WITH ORDINALITY ] [ [ AS ] <replaceable class="parameter">alias</replaceable> [ ( <replaceable class="parameter">column_alias</replaceable> [, ...] ) ] ]
[ LATERAL ] <replaceable class="parameter">function_name</replaceable> ( [ <replaceable class="parameter">argument</replaceable> [, ...] ] ) [ AS ] <replaceable class="parameter">alias</replaceable> ( <replaceable class="parameter">column_definition</replaceable> [, ...] )
[ LATERAL ] <replaceable class="parameter">function_name</replaceable> ( [ <replaceable class="parameter">argument</replaceable> [, ...] ] ) AS ( <replaceable class="parameter">column_definition</replaceable> [, ...] )
[ LATERAL ] TABLE( <replaceable class="parameter">function_name</replaceable> ( [ <replaceable class="parameter">argument</replaceable> [, ...] ] ) [ AS ( <replaceable class="parameter">column_definition</replaceable> [, ...] ) ] [, ...] )
[ LATERAL ] ROWS FROM( <replaceable class="parameter">function_name</replaceable> ( [ <replaceable class="parameter">argument</replaceable> [, ...] ] ) [ AS ( <replaceable class="parameter">column_definition</replaceable> [, ...] ) ] [, ...] )
[ WITH ORDINALITY ] [ [ AS ] <replaceable class="parameter">alias</replaceable> [ ( <replaceable class="parameter">column_alias</replaceable> [, ...] ) ] ]
<replaceable class="parameter">from_item</replaceable> [ NATURAL ] <replaceable class="parameter">join_type</replaceable> <replaceable class="parameter">from_item</replaceable> [ ON <replaceable class="parameter">join_condition</replaceable> | USING ( <replaceable class="parameter">join_column</replaceable> [, ...] ) ]
@ -390,7 +390,7 @@ TABLE [ ONLY ] <replaceable class="parameter">table_name</replaceable> [ * ]
<para>
Multiple function calls can be combined into a
single <literal>FROM</>-clause item by surrounding them
with <literal>TABLE( ... )</>. The output of such an item is the
with <literal>ROWS FROM( ... )</>. The output of such an item is the
concatenation of the first row from each function, then the second
row from each function, etc. If some of the functions produce fewer
rows than others, NULLs are substituted for the missing data, so
@ -410,18 +410,18 @@ TABLE [ ONLY ] <replaceable class="parameter">table_name</replaceable> [ * ]
</para>
<para>
When using the <literal>TABLE( ... )</> syntax, if one of the
When using the <literal>ROWS FROM( ... )</> syntax, if one of the
functions requires a column definition list, it's preferred to put
the column definition list after the function call inside
<literal>TABLE( ... )</>. A column definition list can be placed
after the <literal>TABLE( ... )</> construct only if there's just a
single function and no <literal>WITH ORDINALITY</> clause.
<literal>ROWS FROM( ... )</>. A column definition list can be placed
after the <literal>ROWS FROM( ... )</> construct only if there's just
a single function and no <literal>WITH ORDINALITY</> clause.
</para>
<para>
To use <literal>ORDINALITY</literal> together with a column definition
list, you must use the <literal>TABLE( ... )</> syntax and put the
column definition list inside <literal>TABLE( ... )</>.
list, you must use the <literal>ROWS FROM( ... )</> syntax and put the
column definition list inside <literal>ROWS FROM( ... )</>.
</para>
</listitem>
</varlistentry>
@ -1811,8 +1811,7 @@ SELECT distributors.* WHERE distributors.name = 'Westward';
</para>
<para>
Placing multiple function calls inside <literal>TABLE( ... )</> syntax is
also an extension of the SQL standard.
<literal>ROWS FROM( ... )</> is an extension of the SQL standard.
</para>
</refsect2>