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CREATE TABLE(7)		PostgreSQL 9.6.3 Documentation	       CREATE TABLE(7)

NAME
       CREATE_TABLE - define a new table

SYNOPSIS
       CREATE [	[ GLOBAL | LOCAL ] { TEMPORARY | TEMP }	| UNLOGGED ] TABLE [ IF	NOT EXISTS ] table_name	( [
	 { column_name data_type [ COLLATE collation ] [ column_constraint [ ... ] ]
	   | table_constraint
	   | LIKE source_table [ like_option ... ] }
	   [, ... ]
       ] )
       [ INHERITS ( parent_table [, ...	] ) ]
       [ WITH (	storage_parameter [= value] [, ... ] ) | WITH OIDS | WITHOUT OIDS ]
       [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP	} ]
       [ TABLESPACE tablespace_name ]

       CREATE [	[ GLOBAL | LOCAL ] { TEMPORARY | TEMP }	| UNLOGGED ] TABLE [ IF	NOT EXISTS ] table_name
	   OF type_name	[ (
	 { column_name WITH OPTIONS [ column_constraint	[ ... ]	]
	   | table_constraint }
	   [, ... ]
       ) ]
       [ WITH (	storage_parameter [= value] [, ... ] ) | WITH OIDS | WITHOUT OIDS ]
       [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP	} ]
       [ TABLESPACE tablespace_name ]

       where column_constraint is:

       [ CONSTRAINT constraint_name ]
       { NOT NULL |
	 NULL |
	 CHECK ( expression ) [	NO INHERIT ] |
	 DEFAULT default_expr |
	 UNIQUE	index_parameters |
	 PRIMARY KEY index_parameters |
	 REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ]
	   [ ON	DELETE action ]	[ ON UPDATE action ] }
       [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY	IMMEDIATE ]

       and table_constraint is:

       [ CONSTRAINT constraint_name ]
       { CHECK ( expression ) [	NO INHERIT ] |
	 UNIQUE	( column_name [, ... ] ) index_parameters |
	 PRIMARY KEY ( column_name [, ... ] ) index_parameters |
	 EXCLUDE [ USING index_method ]	( exclude_element WITH operator	[, ... ] ) index_parameters [ WHERE ( predicate	) ] |
	 FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn	[, ... ] ) ]
	   [ MATCH FULL	| MATCH	PARTIAL	| MATCH	SIMPLE ] [ ON DELETE action ] [	ON UPDATE action ] }
       [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY	IMMEDIATE ]

       and like_option is:

       { INCLUDING | EXCLUDING } { DEFAULTS | CONSTRAINTS | INDEXES | STORAGE |	COMMENTS | ALL }

       index_parameters	in UNIQUE, PRIMARY KEY,	and EXCLUDE constraints	are:

       [ WITH (	storage_parameter [= value] [, ... ] ) ]
       [ USING INDEX TABLESPACE	tablespace_name	]

       exclude_element in an EXCLUDE constraint	is:

       { column_name | ( expression ) }	[ opclass ] [ ASC | DESC ] [ NULLS { FIRST | LAST } ]

DESCRIPTION
       CREATE TABLE will create	a new, initially empty table in	the current
       database. The table will	be owned by the	user issuing the command.

       If a schema name	is given (for example, CREATE TABLE myschema.mytable
       ...) then the table is created in the specified schema. Otherwise it is
       created in the current schema. Temporary	tables exist in	a special
       schema, so a schema name	cannot be given	when creating a	temporary
       table. The name of the table must be distinct from the name of any
       other table, sequence, index, view, or foreign table in the same
       schema.

       CREATE TABLE also automatically creates a data type that	represents the
       composite type corresponding to one row of the table. Therefore,	tables
       cannot have the same name as any	existing data type in the same schema.

       The optional constraint clauses specify constraints (tests) that	new or
       updated rows must satisfy for an	insert or update operation to succeed.
       A constraint is an SQL object that helps	define the set of valid	values
       in the table in various ways.

       There are two ways to define constraints: table constraints and column
       constraints. A column constraint	is defined as part of a	column
       definition. A table constraint definition is not	tied to	a particular
       column, and it can encompass more than one column. Every	column
       constraint can also be written as a table constraint; a column
       constraint is only a notational convenience for use when	the constraint
       only affects one	column.

       To be able to create a table, you must have USAGE privilege on all
       column types or the type	in the OF clause, respectively.

PARAMETERS
       TEMPORARY or TEMP
	   If specified, the table is created as a temporary table. Temporary
	   tables are automatically dropped at the end of a session, or
	   optionally at the end of the	current	transaction (see ON COMMIT
	   below). Existing permanent tables with the same name	are not
	   visible to the current session while	the temporary table exists,
	   unless they are referenced with schema-qualified names. Any indexes
	   created on a	temporary table	are automatically temporary as well.

	   The autovacuum daemon cannot	access and therefore cannot vacuum or
	   analyze temporary tables. For this reason, appropriate vacuum and
	   analyze operations should be	performed via session SQL commands.
	   For example,	if a temporary table is	going to be used in complex
	   queries, it is wise to run ANALYZE on the temporary table after it
	   is populated.

	   Optionally, GLOBAL or LOCAL can be written before TEMPORARY or
	   TEMP. This presently	makes no difference in PostgreSQL and is
	   deprecated; see COMPATIBILITY.

       UNLOGGED
	   If specified, the table is created as an unlogged table. Data
	   written to unlogged tables is not written to	the write-ahead	log
	   (see	Chapter	30, Reliability	and the	Write-Ahead Log, in the
	   documentation), which makes them considerably faster	than ordinary
	   tables. However, they are not crash-safe: an	unlogged table is
	   automatically truncated after a crash or unclean shutdown. The
	   contents of an unlogged table are also not replicated to standby
	   servers. Any	indexes	created	on an unlogged table are automatically
	   unlogged as well.

       IF NOT EXISTS
	   Do not throw	an error if a relation with the	same name already
	   exists. A notice is issued in this case. Note that there is no
	   guarantee that the existing relation	is anything like the one that
	   would have been created.

       table_name
	   The name (optionally	schema-qualified) of the table to be created.

       OF type_name
	   Creates a typed table, which	takes its structure from the specified
	   composite type (name	optionally schema-qualified). A	typed table is
	   tied	to its type; for example the table will	be dropped if the type
	   is dropped (with DROP TYPE ... CASCADE).

	   When	a typed	table is created, then the data	types of the columns
	   are determined by the underlying composite type and are not
	   specified by	the CREATE TABLE command. But the CREATE TABLE command
	   can add defaults and	constraints to the table and can specify
	   storage parameters.

       column_name
	   The name of a column	to be created in the new table.

       data_type
	   The data type of the	column.	This can include array specifiers. For
	   more	information on the data	types supported	by PostgreSQL, refer
	   to Chapter 8, Data Types, in	the documentation.

       COLLATE collation
	   The COLLATE clause assigns a	collation to the column	(which must be
	   of a	collatable data	type). If not specified, the column data
	   type's default collation is used.

       INHERITS	( parent_table [, ... ]	)
	   The optional	INHERITS clause	specifies a list of tables from	which
	   the new table automatically inherits	all columns. Parent tables can
	   be plain tables or foreign tables.

	   Use of INHERITS creates a persistent	relationship between the new
	   child table and its parent table(s).	Schema modifications to	the
	   parent(s) normally propagate	to children as well, and by default
	   the data of the child table is included in scans of the parent(s).

	   If the same column name exists in more than one parent table, an
	   error is reported unless the	data types of the columns match	in
	   each	of the parent tables. If there is no conflict, then the
	   duplicate columns are merged	to form	a single column	in the new
	   table. If the column	name list of the new table contains a column
	   name	that is	also inherited,	the data type must likewise match the
	   inherited column(s),	and the	column definitions are merged into
	   one.	If the new table explicitly specifies a	default	value for the
	   column, this	default	overrides any defaults from inherited
	   declarations	of the column. Otherwise, any parents that specify
	   default values for the column must all specify the same default, or
	   an error will be reported.

	   CHECK constraints are merged	in essentially the same	way as
	   columns: if multiple	parent tables and/or the new table definition
	   contain identically-named CHECK constraints,	these constraints must
	   all have the	same check expression, or an error will	be reported.
	   Constraints having the same name and	expression will	be merged into
	   one copy. A constraint marked NO INHERIT in a parent	will not be
	   considered. Notice that an unnamed CHECK constraint in the new
	   table will never be merged, since a unique name will	always be
	   chosen for it.

	   Column STORAGE settings are also copied from	parent tables.

       LIKE source_table [ like_option ... ]
	   The LIKE clause specifies a table from which	the new	table
	   automatically copies	all column names, their	data types, and	their
	   not-null constraints.

	   Unlike INHERITS, 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.

	   Default expressions for the copied column definitions will be
	   copied only if INCLUDING DEFAULTS is	specified. The default
	   behavior is to exclude default expressions, resulting in the	copied
	   columns in the new table having null	defaults. Note that copying
	   defaults that call database-modification functions, such as
	   nextval, may	create a functional linkage between the	original and
	   new tables.

	   Not-null constraints	are always copied to the new table.  CHECK
	   constraints will be copied only if INCLUDING	CONSTRAINTS is
	   specified. No distinction is	made between column constraints	and
	   table constraints.

	   Indexes, PRIMARY KEY, UNIQUE, and EXCLUDE constraints on the
	   original table will be created on the new table only	if INCLUDING
	   INDEXES is specified. Names for the new indexes and constraints are
	   chosen according to the default rules, regardless of	how the
	   originals were named. (This behavior	avoids possible	duplicate-name
	   failures for	the new	indexes.)

	   STORAGE settings for	the copied column definitions will be copied
	   only	if INCLUDING STORAGE is	specified. The default behavior	is to
	   exclude STORAGE settings, resulting in the copied columns in	the
	   new table having type-specific default settings. For	more on
	   STORAGE settings, see Section 65.2, "TOAST",	in the documentation.

	   Comments for	the copied columns, constraints, and indexes will be
	   copied only if INCLUDING COMMENTS is	specified. The default
	   behavior is to exclude comments, resulting in the copied columns
	   and constraints in the new table having no comments.

	   INCLUDING ALL is an abbreviated form	of INCLUDING DEFAULTS
	   INCLUDING CONSTRAINTS INCLUDING INDEXES INCLUDING STORAGE INCLUDING
	   COMMENTS.

	   Note	that unlike INHERITS, columns and constraints copied by	LIKE
	   are not merged with similarly named columns and constraints.	If the
	   same	name is	specified explicitly or	in another LIKE	clause,	an
	   error is signaled.

	   The LIKE clause can also be used to copy column definitions from
	   views, foreign tables, or composite types. Inapplicable options
	   (e.g., INCLUDING INDEXES from a view) are ignored.

       CONSTRAINT constraint_name
	   An optional name for	a column or table constraint. If the
	   constraint is violated, the constraint name is present in error
	   messages, so	constraint names like col must be positive can be used
	   to communicate helpful constraint information to client
	   applications. (Double-quotes	are needed to specify constraint names
	   that	contain	spaces.) If a constraint name is not specified,	the
	   system generates a name.

       NOT NULL
	   The column is not allowed to	contain	null values.

       NULL
	   The column is allowed to contain null values. This is the default.

	   This	clause is only provided	for compatibility with non-standard
	   SQL databases. Its use is discouraged in new	applications.

       CHECK ( expression ) [ NO INHERIT ]
	   The CHECK clause specifies an expression producing a	Boolean	result
	   which new or	updated	rows must satisfy for an insert	or update
	   operation to	succeed. Expressions evaluating	to TRUE	or UNKNOWN
	   succeed. Should any row of an insert	or update operation produce a
	   FALSE result, an error exception is raised and the insert or	update
	   does	not alter the database.	A check	constraint specified as	a
	   column constraint should reference that column's value only,	while
	   an expression appearing in a	table constraint can reference
	   multiple columns.

	   Currently, CHECK expressions	cannot contain subqueries nor refer to
	   variables other than	columns	of the current row. The	system column
	   tableoid may	be referenced, but not any other system	column.

	   A constraint	marked with NO INHERIT will not	propagate to child
	   tables.

	   When	a table	has multiple CHECK constraints,	they will be tested
	   for each row	in alphabetical	order by name, after checking NOT NULL
	   constraints.	(PostgreSQL versions before 9.5	did not	honor any
	   particular firing order for CHECK constraints.)

       DEFAULT default_expr
	   The DEFAULT clause assigns a	default	data value for the column
	   whose column	definition it appears within. The value	is any
	   variable-free expression (subqueries	and cross-references to	other
	   columns in the current table	are not	allowed). The data type	of the
	   default expression must match the data type of the column.

	   The default expression will be used in any insert operation that
	   does	not specify a value for	the column. If there is	no default for
	   a column, then the default is null.

       UNIQUE (column constraint)
       UNIQUE (	column_name [, ... ] ) (table constraint)
	   The UNIQUE constraint specifies that	a group	of one or more columns
	   of a	table can contain only unique values. The behavior of the
	   unique table	constraint is the same as that for column constraints,
	   with	the additional capability to span multiple columns.

	   For the purpose of a	unique constraint, null	values are not
	   considered equal.

	   Each	unique table constraint	must name a set	of columns that	is
	   different from the set of columns named by any other	unique or
	   primary key constraint defined for the table. (Otherwise it would
	   just	be the same constraint listed twice.)

       PRIMARY KEY (column constraint)
       PRIMARY KEY ( column_name [, ...	] ) (table constraint)
	   The PRIMARY KEY constraint specifies	that a column or columns of a
	   table can contain only unique (non-duplicate), nonnull values. Only
	   one primary key can be specified for	a table, whether as a column
	   constraint or a table constraint.

	   The primary key constraint should name a set	of columns that	is
	   different from the set of columns named by any unique constraint
	   defined for the same	table. (Otherwise, the unique constraint is
	   redundant and will be discarded.)

	   PRIMARY KEY enforces	the same data constraints as a combination of
	   UNIQUE and NOT NULL,	but identifying	a set of columns as the
	   primary key also provides metadata about the	design of the schema,
	   since a primary key implies that other tables can rely on this set
	   of columns as a unique identifier for rows.

       EXCLUDE [ USING index_method ] (	exclude_element	WITH operator [, ... ]
       ) index_parameters [ WHERE ( predicate )	]
	   The EXCLUDE clause defines an exclusion constraint, which
	   guarantees that if any two rows are compared	on the specified
	   column(s) or	expression(s) using the	specified operator(s), not all
	   of these comparisons	will return TRUE. If all of the	specified
	   operators test for equality,	this is	equivalent to a	UNIQUE
	   constraint, although	an ordinary unique constraint will be faster.
	   However, exclusion constraints can specify constraints that are
	   more	general	than simple equality. For example, you can specify a
	   constraint that no two rows in the table contain overlapping
	   circles (see	Section	8.8, "Geometric	Types",	in the documentation)
	   by using the	&& operator.

	   Exclusion constraints are implemented using an index, so each
	   specified operator must be associated with an appropriate operator
	   class (see Section 11.9, "Operator Classes and Operator Families",
	   in the documentation) for the index access method index_method. The
	   operators are required to be	commutative. Each exclude_element can
	   optionally specify an operator class	and/or ordering	options; these
	   are described fully under CREATE INDEX (CREATE_INDEX(7)).

	   The access method must support amgettuple (see Chapter 59, Index
	   Access Method Interface Definition, in the documentation); at
	   present this	means GIN cannot be used. Although it's	allowed, there
	   is little point in using B-tree or hash indexes with	an exclusion
	   constraint, because this does nothing that an ordinary unique
	   constraint doesn't do better. So in practice	the access method will
	   always be GiST or SP-GiST.

	   The predicate allows	you to specify an exclusion constraint on a
	   subset of the table;	internally this	creates	a partial index. Note
	   that	parentheses are	required around	the predicate.

       REFERENCES reftable [ ( refcolumn ) ] [ MATCH matchtype ] [ ON DELETE
       action ]	[ ON UPDATE action ] (column constraint)
       FOREIGN KEY ( column_name [, ...	] ) REFERENCES reftable	[ ( refcolumn
       [, ... ]	) ] [ MATCH matchtype ]	[ ON DELETE action ] [ ON UPDATE
       action ]	(table constraint)
	   These clauses specify a foreign key constraint, which requires that
	   a group of one or more columns of the new table must	only contain
	   values that match values in the referenced column(s)	of some	row of
	   the referenced table. If the	refcolumn list is omitted, the primary
	   key of the reftable is used.	The referenced columns must be the
	   columns of a	non-deferrable unique or primary key constraint	in the
	   referenced table. Note that foreign key constraints cannot be
	   defined between temporary tables and	permanent tables.

	   A value inserted into the referencing column(s) is matched against
	   the values of the referenced	table and referenced columns using the
	   given match type. There are three match types: MATCH	FULL, MATCH
	   PARTIAL, and	MATCH SIMPLE (which is the default).  MATCH FULL will
	   not allow one column	of a multicolumn foreign key to	be null	unless
	   all foreign key columns are null; if	they are all null, the row is
	   not required	to have	a match	in the referenced table.  MATCH	SIMPLE
	   allows any of the foreign key columns to be null; if	any of them
	   are null, the row is	not required to	have a match in	the referenced
	   table.  MATCH PARTIAL is not	yet implemented. (Of course, NOT NULL
	   constraints can be applied to the referencing column(s) to prevent
	   these cases from arising.)

	   In addition,	when the data in the referenced	columns	is changed,
	   certain actions are performed on the	data in	this table's columns.
	   The ON DELETE clause	specifies the action to	perform	when a
	   referenced row in the referenced table is being deleted. Likewise,
	   the ON UPDATE clause	specifies the action to	perform	when a
	   referenced column in	the referenced table is	being updated to a new
	   value. If the row is	updated, but the referenced column is not
	   actually changed, no	action is done.	Referential actions other than
	   the NO ACTION check cannot be deferred, even	if the constraint is
	   declared deferrable.	There are the following	possible actions for
	   each	clause:

	   NO ACTION
	       Produce an error	indicating that	the deletion or	update would
	       create a	foreign	key constraint violation. If the constraint is
	       deferred, this error will be produced at	constraint check time
	       if there	still exist any	referencing rows. This is the default
	       action.

	   RESTRICT
	       Produce an error	indicating that	the deletion or	update would
	       create a	foreign	key constraint violation. This is the same as
	       NO ACTION except	that the check is not deferrable.

	   CASCADE
	       Delete any rows referencing the deleted row, or update the
	       values of the referencing column(s) to the new values of	the
	       referenced columns, respectively.

	   SET NULL
	       Set the referencing column(s) to	null.

	   SET DEFAULT
	       Set the referencing column(s) to	their default values. (There
	       must be a row in	the referenced table matching the default
	       values, if they are not null, or	the operation will fail.)

	   If the referenced column(s) are changed frequently, it might	be
	   wise	to add an index	to the referencing column(s) so	that
	   referential actions associated with the foreign key constraint can
	   be performed	more efficiently.

       DEFERRABLE
       NOT DEFERRABLE
	   This	controls whether the constraint	can be deferred. A constraint
	   that	is not deferrable will be checked immediately after every
	   command. Checking of	constraints that are deferrable	can be
	   postponed until the end of the transaction (using the SET
	   CONSTRAINTS (SET_CONSTRAINTS(7)) command).  NOT DEFERRABLE is the
	   default. Currently, only UNIQUE, PRIMARY KEY, EXCLUDE, and
	   REFERENCES (foreign key) constraints	accept this clause.  NOT NULL
	   and CHECK constraints are not deferrable. Note that deferrable
	   constraints cannot be used as conflict arbitrators in an INSERT
	   statement that includes an ON CONFLICT DO UPDATE clause.

       INITIALLY IMMEDIATE
       INITIALLY DEFERRED
	   If a	constraint is deferrable, this clause specifies	the default
	   time	to check the constraint. If the	constraint is INITIALLY
	   IMMEDIATE, it is checked after each statement. This is the default.
	   If the constraint is	INITIALLY DEFERRED, it is checked only at the
	   end of the transaction. The constraint check	time can be altered
	   with	the SET	CONSTRAINTS (SET_CONSTRAINTS(7)) command.

       WITH ( storage_parameter	[= value] [, ... ] )
	   This	clause specifies optional storage parameters for a table or
	   index; see Storage Parameters for more information. The WITH	clause
	   for a table can also	include	OIDS=TRUE (or just OIDS) to specify
	   that	rows of	the new	table should have OIDs (object identifiers)
	   assigned to them, or	OIDS=FALSE to specify that the rows should not
	   have	OIDs. If OIDS is not specified,	the default setting depends
	   upon	the default_with_oids configuration parameter. (If the new
	   table inherits from any tables that have OIDs, then OIDS=TRUE is
	   forced even if the command says OIDS=FALSE.)

	   If OIDS=FALSE is specified or implied, the new table	does not store
	   OIDs	and no OID will	be assigned for	a row inserted into it.	This
	   is generally	considered worthwhile, since it	will reduce OID
	   consumption and thereby postpone the	wraparound of the 32-bit OID
	   counter. Once the counter wraps around, OIDs	can no longer be
	   assumed to be unique, which makes them considerably less useful. In
	   addition, excluding OIDs from a table reduces the space required to
	   store the table on disk by 4	bytes per row (on most machines),
	   slightly improving performance.

	   To remove OIDs from a table after it	has been created, use ALTER
	   TABLE (ALTER_TABLE(7)).

       WITH OIDS
       WITHOUT OIDS
	   These are obsolescent syntaxes equivalent to	WITH (OIDS) and	WITH
	   (OIDS=FALSE), respectively. If you wish to give both	an OIDS
	   setting and storage parameters, you must use	the WITH ( ... )
	   syntax; see above.

       ON COMMIT
	   The behavior	of temporary tables at the end of a transaction	block
	   can be controlled using ON COMMIT. The three	options	are:

	   PRESERVE ROWS
	       No special action is taken at the ends of transactions. This is
	       the default behavior.

	   DELETE ROWS
	       All rows	in the temporary table will be deleted at the end of
	       each transaction	block. Essentially, an automatic TRUNCATE(7)
	       is done at each commit.

	   DROP
	       The temporary table will	be dropped at the end of the current
	       transaction block.

       TABLESPACE tablespace_name
	   The tablespace_name is the name of the tablespace in	which the new
	   table is to be created. If not specified, default_tablespace	is
	   consulted, or temp_tablespaces if the table is temporary.

       USING INDEX TABLESPACE tablespace_name
	   This	clause allows selection	of the tablespace in which the index
	   associated with a UNIQUE, PRIMARY KEY, or EXCLUDE constraint	will
	   be created. If not specified, default_tablespace is consulted, or
	   temp_tablespaces if the table is temporary.

   Storage Parameters
       The WITH	clause can specify storage parameters for tables, and for
       indexes associated with a UNIQUE, PRIMARY KEY, or EXCLUDE constraint.
       Storage parameters for indexes are documented in	CREATE INDEX
       (CREATE_INDEX(7)). The storage parameters currently available for
       tables are listed below.	For many of these parameters, as shown,	there
       is an additional	parameter with the same	name prefixed with toast.,
       which controls the behavior of the table's secondary TOAST table, if
       any (see	Section	65.2, "TOAST", in the documentation for	more
       information about TOAST). If a table parameter value is set and the
       equivalent toast.  parameter is not, the	TOAST table will use the
       table's parameter value.

       fillfactor (integer)
	   The fillfactor for a	table is a percentage between 10 and 100. 100
	   (complete packing) is the default. When a smaller fillfactor	is
	   specified, INSERT operations	pack table pages only to the indicated
	   percentage; the remaining space on each page	is reserved for
	   updating rows on that page. This gives UPDATE a chance to place the
	   updated copy	of a row on the	same page as the original, which is
	   more	efficient than placing it on a different page. For a table
	   whose entries are never updated, complete packing is	the best
	   choice, but in heavily updated tables smaller fillfactors are
	   appropriate.	This parameter cannot be set for TOAST tables.

       parallel_workers	(integer)
	   This	sets the number	of workers that	should be used to assist a
	   parallel scan of this table.	If not set, the	system will determine
	   a value based on the	relation size. The actual number of workers
	   chosen by the planner may be	less, for example due to the setting
	   of max_worker_processes.

       autovacuum_enabled, toast.autovacuum_enabled (boolean)
	   Enables or disables the autovacuum daemon for a particular table.
	   If true, the	autovacuum daemon will perform automatic VACUUM	and/or
	   ANALYZE operations on this table following the rules	discussed in
	   Section 24.1.6, "The	Autovacuum Daemon", in the documentation. If
	   false, this table will not be autovacuumed, except to prevent
	   transaction ID wraparound. See Section 24.1.5, "Preventing
	   Transaction ID Wraparound Failures",	in the documentation for more
	   about wraparound prevention.	Note that the autovacuum daemon	does
	   not run at all (except to prevent transaction ID wraparound)	if the
	   autovacuum parameter	is false; setting individual tables' storage
	   parameters does not override	that. Therefore	there is seldom	much
	   point in explicitly setting this storage parameter to true, only to
	   false.

       autovacuum_vacuum_threshold, toast.autovacuum_vacuum_threshold
       (integer)
	   Per-table value for autovacuum_vacuum_threshold parameter.

       autovacuum_vacuum_scale_factor, toast.autovacuum_vacuum_scale_factor
       (float4)
	   Per-table value for autovacuum_vacuum_scale_factor parameter.

       autovacuum_analyze_threshold (integer)
	   Per-table value for autovacuum_analyze_threshold parameter.

       autovacuum_analyze_scale_factor (float4)
	   Per-table value for autovacuum_analyze_scale_factor parameter.

       autovacuum_vacuum_cost_delay, toast.autovacuum_vacuum_cost_delay
       (integer)
	   Per-table value for autovacuum_vacuum_cost_delay parameter.

       autovacuum_vacuum_cost_limit, toast.autovacuum_vacuum_cost_limit
       (integer)
	   Per-table value for autovacuum_vacuum_cost_limit parameter.

       autovacuum_freeze_min_age, toast.autovacuum_freeze_min_age (integer)
	   Per-table value for vacuum_freeze_min_age parameter.	Note that
	   autovacuum will ignore per-table autovacuum_freeze_min_age
	   parameters that are larger than half	the system-wide
	   autovacuum_freeze_max_age setting.

       autovacuum_freeze_max_age, toast.autovacuum_freeze_max_age (integer)
	   Per-table value for autovacuum_freeze_max_age parameter. Note that
	   autovacuum will ignore per-table autovacuum_freeze_max_age
	   parameters that are larger than the system-wide setting (it can
	   only	be set smaller).

       autovacuum_freeze_table_age, toast.autovacuum_freeze_table_age
       (integer)
	   Per-table value for vacuum_freeze_table_age parameter.

       autovacuum_multixact_freeze_min_age,
       toast.autovacuum_multixact_freeze_min_age (integer)
	   Per-table value for vacuum_multixact_freeze_min_age parameter. Note
	   that	autovacuum will	ignore per-table
	   autovacuum_multixact_freeze_min_age parameters that are larger than
	   half	the system-wide	autovacuum_multixact_freeze_max_age setting.

       autovacuum_multixact_freeze_max_age,
       toast.autovacuum_multixact_freeze_max_age (integer)
	   Per-table value for autovacuum_multixact_freeze_max_age parameter.
	   Note	that autovacuum	will ignore per-table
	   autovacuum_multixact_freeze_max_age parameters that are larger than
	   the system-wide setting (it can only	be set smaller).

       autovacuum_multixact_freeze_table_age,
       toast.autovacuum_multixact_freeze_table_age (integer)
	   Per-table value for vacuum_multixact_freeze_table_age parameter.

       log_autovacuum_min_duration, toast.log_autovacuum_min_duration
       (integer)
	   Per-table value for log_autovacuum_min_duration parameter.

       user_catalog_table (boolean)
	   Declare the table as	an additional catalog table for	purposes of
	   logical replication.	See Section 47.6.2, "Capabilities", in the
	   documentation for details. This parameter cannot be set for TOAST
	   tables.

NOTES
       Using OIDs in new applications is not recommended: where	possible,
       using a SERIAL or other sequence	generator as the table's primary key
       is preferred. However, if your application does make use	of OIDs	to
       identify	specific rows of a table, it is	recommended to create a	unique
       constraint on the oid column of that table, to ensure that OIDs in the
       table will indeed uniquely identify rows	even after counter wraparound.
       Avoid assuming that OIDs	are unique across tables; if you need a
       database-wide unique identifier,	use the	combination of tableoid	and
       row OID for the purpose.

	   Tip
	   The use of OIDS=FALSE is not	recommended for	tables with no primary
	   key,	since without either an	OID or a unique	data key, it is
	   difficult to	identify specific rows.

       PostgreSQL automatically	creates	an index for each unique constraint
       and primary key constraint to enforce uniqueness. Thus, it is not
       necessary to create an index explicitly for primary key columns.	(See
       CREATE INDEX (CREATE_INDEX(7)) for more information.)

       Unique constraints and primary keys are not inherited in	the current
       implementation. This makes the combination of inheritance and unique
       constraints rather dysfunctional.

       A table cannot have more	than 1600 columns. (In practice, the effective
       limit is	usually	lower because of tuple-length constraints.)

EXAMPLES
       Create table films and table distributors:

	   CREATE TABLE	films (
	       code	   char(5) CONSTRAINT firstkey PRIMARY KEY,
	       title	   varchar(40) NOT NULL,
	       did	   integer NOT NULL,
	       date_prod   date,
	       kind	   varchar(10),
	       len	   interval hour to minute
	   );

	   CREATE TABLE	distributors (
		did    integer PRIMARY KEY DEFAULT nextval('serial'),
		name   varchar(40) NOT NULL CHECK (name	<> '')
	   );

       Create a	table with a 2-dimensional array:

	   CREATE TABLE	array_int (
	       vector  int[][]
	   );

       Define a	unique table constraint	for the	table films. Unique table
       constraints can be defined on one or more columns of the	table:

	   CREATE TABLE	films (
	       code	   char(5),
	       title	   varchar(40),
	       did	   integer,
	       date_prod   date,
	       kind	   varchar(10),
	       len	   interval hour to minute,
	       CONSTRAINT production UNIQUE(date_prod)
	   );

       Define a	check column constraint:

	   CREATE TABLE	distributors (
	       did     integer CHECK (did > 100),
	       name    varchar(40)
	   );

       Define a	check table constraint:

	   CREATE TABLE	distributors (
	       did     integer,
	       name    varchar(40)
	       CONSTRAINT con1 CHECK (did > 100	AND name <> '')
	   );

       Define a	primary	key table constraint for the table films:

	   CREATE TABLE	films (
	       code	   char(5),
	       title	   varchar(40),
	       did	   integer,
	       date_prod   date,
	       kind	   varchar(10),
	       len	   interval hour to minute,
	       CONSTRAINT code_title PRIMARY KEY(code,title)
	   );

       Define a	primary	key constraint for table distributors. The following
       two examples are	equivalent, the	first using the	table constraint
       syntax, the second the column constraint	syntax:

	   CREATE TABLE	distributors (
	       did     integer,
	       name    varchar(40),
	       PRIMARY KEY(did)
	   );

	   CREATE TABLE	distributors (
	       did     integer PRIMARY KEY,
	       name    varchar(40)
	   );

       Assign a	literal	constant default value for the column name, arrange
       for the default value of	column did to be generated by selecting	the
       next value of a sequence	object,	and make the default value of modtime
       be the time at which the	row is inserted:

	   CREATE TABLE	distributors (
	       name	 varchar(40) DEFAULT 'Luso Films',
	       did	 integer DEFAULT nextval('distributors_serial'),
	       modtime	 timestamp DEFAULT current_timestamp
	   );

       Define two NOT NULL column constraints on the table distributors, one
       of which	is explicitly given a name:

	   CREATE TABLE	distributors (
	       did     integer CONSTRAINT no_null NOT NULL,
	       name    varchar(40) NOT NULL
	   );

       Define a	unique constraint for the name column:

	   CREATE TABLE	distributors (
	       did     integer,
	       name    varchar(40) UNIQUE
	   );

       The same, specified as a	table constraint:

	   CREATE TABLE	distributors (
	       did     integer,
	       name    varchar(40),
	       UNIQUE(name)
	   );

       Create the same table, specifying 70% fill factor for both the table
       and its unique index:

	   CREATE TABLE	distributors (
	       did     integer,
	       name    varchar(40),
	       UNIQUE(name) WITH (fillfactor=70)
	   )
	   WITH	(fillfactor=70);

       Create table circles with an exclusion constraint that prevents any two
       circles from overlapping:

	   CREATE TABLE	circles	(
	       c circle,
	       EXCLUDE USING gist (c WITH &&)
	   );

       Create table cinemas in tablespace diskvol1:

	   CREATE TABLE	cinemas	(
		   id serial,
		   name	text,
		   location text
	   ) TABLESPACE	diskvol1;

       Create a	composite type and a typed table:

	   CREATE TYPE employee_type AS	(name text, salary numeric);

	   CREATE TABLE	employees OF employee_type (
	       PRIMARY KEY (name),
	       salary WITH OPTIONS DEFAULT 1000
	   );

COMPATIBILITY
       The CREATE TABLE	command	conforms to the	SQL standard, with exceptions
       listed below.

   Temporary Tables
       Although	the syntax of CREATE TEMPORARY TABLE resembles that of the SQL
       standard, the effect is not the same. In	the standard, temporary	tables
       are defined just	once and automatically exist (starting with empty
       contents) in every session that needs them.  PostgreSQL instead
       requires	each session to	issue its own CREATE TEMPORARY TABLE command
       for each	temporary table	to be used. This allows	different sessions to
       use the same temporary table name for different purposes, whereas the
       standard's approach constrains all instances of a given temporary table
       name to have the	same table structure.

       The standard's definition of the	behavior of temporary tables is	widely
       ignored.	 PostgreSQL's behavior on this point is	similar	to that	of
       several other SQL databases.

       The SQL standard	also distinguishes between global and local temporary
       tables, where a local temporary table has a separate set	of contents
       for each	SQL module within each session,	though its definition is still
       shared across sessions. Since PostgreSQL	does not support SQL modules,
       this distinction	is not relevant	in PostgreSQL.

       For compatibility's sake, PostgreSQL will accept	the GLOBAL and LOCAL
       keywords	in a temporary table declaration, but they currently have no
       effect. Use of these keywords is	discouraged, since future versions of
       PostgreSQL might	adopt a	more standard-compliant	interpretation of
       their meaning.

       The ON COMMIT clause for	temporary tables also resembles	the SQL
       standard, but has some differences. If the ON COMMIT clause is omitted,
       SQL specifies that the default behavior is ON COMMIT DELETE ROWS.
       However,	the default behavior in	PostgreSQL is ON COMMIT	PRESERVE ROWS.
       The ON COMMIT DROP option does not exist	in SQL.

   Non-deferred	Uniqueness Constraints
       When a UNIQUE or	PRIMARY	KEY constraint is not deferrable, PostgreSQL
       checks for uniqueness immediately whenever a row	is inserted or
       modified. The SQL standard says that uniqueness should be enforced only
       at the end of the statement; this makes a difference when, for example,
       a single	command	updates	multiple key values. To	obtain
       standard-compliant behavior, declare the	constraint as DEFERRABLE but
       not deferred (i.e., INITIALLY IMMEDIATE). Be aware that this can	be
       significantly slower than immediate uniqueness checking.

   Column Check	Constraints
       The SQL standard	says that CHECK	column constraints can only refer to
       the column they apply to; only CHECK table constraints can refer	to
       multiple	columns.  PostgreSQL does not enforce this restriction;	it
       treats column and table check constraints alike.

   EXCLUDE Constraint
       The EXCLUDE constraint type is a	PostgreSQL extension.

   NULL	"Constraint"
       The NULL"constraint" (actually a	non-constraint)	is a PostgreSQL
       extension to the	SQL standard that is included for compatibility	with
       some other database systems (and	for symmetry with the NOT NULL
       constraint). Since it is	the default for	any column, its	presence is
       simply noise.

   Inheritance
       Multiple	inheritance via	the INHERITS clause is a PostgreSQL language
       extension. SQL:1999 and later define single inheritance using a
       different syntax	and different semantics. SQL:1999-style	inheritance is
       not yet supported by PostgreSQL.

   Zero-column Tables
       PostgreSQL allows a table of no columns to be created (for example,
       CREATE TABLE foo();). This is an	extension from the SQL standard, which
       does not	allow zero-column tables. Zero-column tables are not in
       themselves very useful, but disallowing them creates odd	special	cases
       for ALTER TABLE DROP COLUMN, so it seems	cleaner	to ignore this spec
       restriction.

   LIKE	Clause
       While a LIKE clause exists in the SQL standard, many of the options
       that PostgreSQL accepts for it are not in the standard, and some	of the
       standard's options are not implemented by PostgreSQL.

   WITH	Clause
       The WITH	clause is a PostgreSQL extension; neither storage parameters
       nor OIDs	are in the standard.

   Tablespaces
       The PostgreSQL concept of tablespaces is	not part of the	standard.
       Hence, the clauses TABLESPACE and USING INDEX TABLESPACE	are
       extensions.

   Typed Tables
       Typed tables implement a	subset of the SQL standard. According to the
       standard, a typed table has columns corresponding to the	underlying
       composite type as well as one other column that is the
       "self-referencing column". PostgreSQL does not support these
       self-referencing	columns	explicitly, but	the same effect	can be had
       using the OID feature.

SEE ALSO
       ALTER TABLE (ALTER_TABLE(7)), DROP TABLE	(DROP_TABLE(7)), CREATE	TABLE
       AS (CREATE_TABLE_AS(7)),	CREATE TABLESPACE (CREATE_TABLESPACE(7)),
       CREATE TYPE (CREATE_TYPE(7))

PostgreSQL 9.6.3		     2017		       CREATE TABLE(7)

NAME | SYNOPSIS | DESCRIPTION | PARAMETERS | NOTES | EXAMPLES | COMPATIBILITY | SEE ALSO

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