diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/ref/create_foreign_table.sgml | 114 |
1 files changed, 113 insertions, 1 deletions
diff --git a/doc/src/sgml/ref/create_foreign_table.sgml b/doc/src/sgml/ref/create_foreign_table.sgml index e0b0e075c2c..d08834ac9d2 100644 --- a/doc/src/sgml/ref/create_foreign_table.sgml +++ b/doc/src/sgml/ref/create_foreign_table.sgml @@ -23,7 +23,8 @@ PostgreSQL documentation <synopsis> CREATE FOREIGN TABLE [ IF NOT EXISTS ] <replaceable class="parameter">table_name</replaceable> ( [ { <replaceable class="parameter">column_name</replaceable> <replaceable class="parameter">data_type</replaceable> [ OPTIONS ( <replaceable class="parameter">option</replaceable> '<replaceable class="parameter">value</replaceable>' [, ... ] ) ] [ COLLATE <replaceable>collation</replaceable> ] [ <replaceable class="parameter">column_constraint</replaceable> [ ... ] ] - | <replaceable>table_constraint</replaceable> } + | <replaceable>table_constraint</replaceable> + | LIKE <replaceable>source_table</replaceable> [ <replaceable>like_option</replaceable> ... ] } [, ... ] ] ) [ INHERITS ( <replaceable>parent_table</replaceable> [, ... ] ) ] @@ -57,6 +58,10 @@ CREATE FOREIGN TABLE [ IF NOT EXISTS ] <replaceable class="parameter">table_name CHECK ( <replaceable class="parameter">expression</replaceable> ) [ NO INHERIT ] } [ ENFORCED | NOT ENFORCED ] +<phrase>and <replaceable class="parameter">like_option</replaceable> is:</phrase> + +{ INCLUDING | EXCLUDING } { COMMENTS | CONSTRAINTS | DEFAULTS | GENERATED | STATISTICS | ALL } + <phrase>and <replaceable class="parameter">partition_bound_spec</replaceable> is:</phrase> IN ( <replaceable class="parameter">partition_bound_expr</replaceable> [, ...] ) | @@ -192,6 +197,111 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM </varlistentry> <varlistentry> + <term><literal>LIKE <replaceable>source_table</replaceable> [ <replaceable>like_option</replaceable> ... ]</literal></term> + <listitem> + <para> + The <literal>LIKE</literal> clause specifies a table from which + the new table automatically copies all column names, their data types, + and their not-null constraints. + </para> + <para> + Unlike <literal>INHERITS</literal>, the new table and original table + are completely decoupled after creation is complete. Changes to the + original table will not be applied to the new table, and it is not + possible to include data of the new table in scans of the original + table. + </para> + <para> + Also unlike <literal>INHERITS</literal>, columns and + constraints copied by <literal>LIKE</literal> are not merged with similarly + named columns and constraints. + If the same name is specified explicitly or in another + <literal>LIKE</literal> clause, an error is signaled. + </para> + <para> + The optional <replaceable>like_option</replaceable> clauses specify + which additional properties of the original table to copy. Specifying + <literal>INCLUDING</literal> copies the property, specifying + <literal>EXCLUDING</literal> omits the property. + <literal>EXCLUDING</literal> is the default. If multiple specifications + are made for the same kind of object, the last one is used. The + available options are: + + <variablelist> + <varlistentry> + <term><literal>INCLUDING COMMENTS</literal></term> + <listitem> + <para> + Comments for the copied columns, constraints, and indexes will be + copied. The default behavior is to exclude comments, resulting in + the copied columns and constraints in the new table having no + comments. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><literal>INCLUDING CONSTRAINTS</literal></term> + <listitem> + <para> + <literal>CHECK</literal> constraints will be copied. No distinction + is made between column constraints and table constraints. Not-null + constraints are always copied to the new table. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><literal>INCLUDING DEFAULTS</literal></term> + <listitem> + <para> + Default expressions for the copied column definitions will be + copied. Otherwise, default expressions are not copied, resulting in + the copied columns in the new table having null defaults. Note that + copying defaults that call database-modification functions, such as + <function>nextval</function>, may create a functional linkage + between the original and new tables. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><literal>INCLUDING GENERATED</literal></term> + <listitem> + <para> + Any generation expressions of copied column definitions will be + copied. By default, new columns will be regular base columns. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><literal>INCLUDING STATISTICS</literal></term> + <listitem> + <para> + Extended statistics are copied to the new table. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><literal>INCLUDING ALL</literal></term> + <listitem> + <para> + <literal>INCLUDING ALL</literal> is an abbreviated form selecting + all the available individual options. (It could be useful to write + individual <literal>EXCLUDING</literal> clauses after + <literal>INCLUDING ALL</literal> to select all but some specific + options.) + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + </listitem> + </varlistentry> + + <varlistentry> <term><literal>CONSTRAINT <replaceable class="parameter">constraint_name</replaceable></literal></term> <listitem> <para> @@ -448,6 +558,8 @@ CREATE FOREIGN TABLE measurement_y2016m07 The ability to specify column default values is also a <productname>PostgreSQL</productname> extension. Table inheritance, in the form defined by <productname>PostgreSQL</productname>, is nonstandard. + The <literal>LIKE</literal> clause, as supported in this command, is + nonstandard. </para> </refsect1> |