Ask a Question
Report a Bug
This page in other versions:
This document in other formats:
Use the Sequence dialog to create a sequence. A sequence generates unique
values in a sequential order (not necessarily contiguous).
The Sequence dialog organizes the development of a sequence through the
following dialog tabs: General, Definition, and Security. The SQL tab
displays the SQL code generated by dialog selections.
Use the fields in the General tab to identify a sequence:
Use the Name field to add a descriptive name for the sequence. The name will
be displayed in the pgAdmin tree control. The sequence name must be
distinct from the name of any other sequence, table, index, view, or foreign
table in the same schema.
Use the drop-down listbox next to Owner to select the name of the role that
will own the sequence.
Use the drop-down listbox next to Schema to select the schema in which the
sequence will reside.
Store notes about the sequence in the Comment field.
Click the Definition tab to continue.
Use the fields in the Definition tab to define the sequence:
Use the Increment field to specify which value is added to the current
sequence value to create a new value.
Provide a value in the Start field to specify the beginning value of the
sequence. The default starting value is MINVALUE for ascending sequences and
MAXVALUE for descending ones.
Provide a value in the Minimum field to specify the minimum value a sequence
can generate. If this clause is not supplied or NO MINVALUE is specified,
then defaults will be used. The defaults are 1 and -263-1 for ascending and
descending sequences, respectively.
Provide a value in the Maximum field to specify the maximum value for the
sequence. If this clause is not supplied or NO MAXVALUE is specified, then
default values will be used. The defaults are 263-1 and -1 for ascending and
descending sequences, respectively.
Provide a value in the Cache field to specify how many sequence numbers are
to be preallocated and stored in memory for faster access. The minimum value
is 1 (only one value can be generated at a time, i.e., no cache), and this is
also the default.
Move the Cycled switch to the Yes position to allow the sequence to wrap
around when the MAXVALUE or the MINVALUE has been reached by an ascending or
descending sequence respectively. If the limit is reached, the next number
generated will be the MINVALUE or MAXVALUE, respectively. The default is No.
Click the Security tab to continue.
Use the Security tab to assign privileges and define security labels for the
Use the Privileges panel to assign privileges. Click the Add icon (+) to
Select the name of a role that will be granted privileges from the drop-down
listbox in the Grantee field.
Click inside the Privileges field. Check the boxes to the left of one or
more privileges to grant the selected privilege to the specified user.
Select the name of the role from the drop-down listbox in the Grantor
field. The default grantor is the owner of the database.
Click the Add icon (+) to assign additional privileges; to discard a
privilege, click the trash icon to the left of the row and confirm deletion in
the Delete Row popup.
Use the Security Labels panel to define security labels applied to the
sequence. Click the Add icon (+) to add each security label selection:
Specify a security label provider in the Provider field. The named provider
must be loaded and must consent to the proposed labeling operation.
Specify a a security label in the Security Label field. The meaning of a
given label is at the discretion of the label provider. PostgreSQL places no
restrictions on whether or how a label provider must interpret security
labels; it merely provides a mechanism for storing them.
Click the Add icon (+) to assign additional security labels; to discard a
security label, click the trash icon to the left of the row and confirm deletion
in the Delete Row popup.
Click the SQL tab to continue.
Your entries in the Sequence dialog generate a generate a SQL command (see an
example below). Use the SQL tab for review; revisit or switch tabs to make any
changes to the SQL command.
The following is an example of the sql command generated by user selections in
the Sequence dialog:
The example shown demonstrates a sequence named seconds. The sequence will
increase in 5 second increments, and stop when it reaches a maximum value
equal of 60.
Click the Info button (i) to access online help.
Click the Save button to save work.
Click the Cancel button to exit without saving work.
Click the Reset button to restore configuration parameters.