A sequence is a database object that generates unique numbers, mostly used for primary key values. One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]
[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]
[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database. This involves creating and initializing a new single-row table with the name seqname. The generator will be owned by the user issuing the command.

If a schema name is given then the sequence is created in the specified schema.

Otherwise it is created in the current schema (the one at the front of the search path; see CURRENT_SCHEMA()). TEMP sequences exist in a special schema, so a schema name may not be given when creating a TEMP sequence. The sequence name must be distinct from the name of any other sequence, table, index, or view in the same schema.

Names the sequence. The name, including the implicit or explicit qualifier, must not identify a sequence or data area that already exists at the current server. If a qualified function name is specified, the schema-name cannot be QSYS2, QSYS, or SYSIBM.

For more information , please do visit source site:

http://www.sql.org/sq l-databas e/postgresql/manual/sql-create seque nce.htm

Answered by Raksha , an ibibo Master, at 9:32 AM on June 18, 2008

Sequence is a class for objects representing an Oracle sequence. The methods of an instanciated object do allow to access the information within a database's data dictionary and to represent them as SQL create statements and the like using the proper SQL dialect.

$sequence = SQL::Schema::Sequence->new(%at tr);

The new method instanciates a sequence object. The object is an in memory representation of a (possible) oracle sequence. The attributes are given as key value pairs by the hash %attr.

Answered by Arti singh , an ibibo Specialist, at 9:12 AM on June 18, 2008

Sequence is a class for objects representing an Oracle sequence. The methods of an instanciated object do allow to access the information within a database's data dictionary and to represent them as SQL create statements and the like using the proper SQL dialect.

$sequence = SQL::Schema::Sequence->new(%at tr);

The new method instanciates a sequence object. The object is an in memory representation of a (possible) oracle sequence. The attributes are given as key value pairs by the hash %attr.

Answered by Sharad Singh , an ibibo Master, at 3:16 PM on May 27, 2008

A sequence is a database object that generates unique numbers, mostly used for primary key values. One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]
[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]
[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database. This involves creating and initializing a new single-row table with the name seqname. The generator will be owned by the user issuing the command.

Answered by Anju Singh , an ibibo Master, at 5:23 PM on May 24, 2008

Well,

A sequence is a database object that generates unique numbers, mostly used for primary key values.

One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]

[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]

[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database.

This involves creating and initializing a new single-row table with the name seqname.

The generator will be owned by the user issuing the command.

Answered by Ajay Pal , an ibibo Master, at 8:10 AM on May 24, 2008

A sequence is a database object that generates unique numbers, mostly used for primary key values. One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]
[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]
[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database. This involves creating and initializing a new single-row table with the name seqname. The generator will be owned by the user issuing the command.

Answered by Nagendra , an ibibo Master, at 7:18 PM on May 23, 2008

A sequence is a database object that generates unique numbers, mostly used for primary key values. One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]
[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]
[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database. This involves creating and initializing a new single-row table with the name seqname. The generator will be owned by the user issuing the command.

If a schema name is given then the sequence is created in the specified schema.

Otherwise it is created in the current schema (the one at the front of the search path; see CURRENT_SCHEMA()). TEMP sequences exist in a special schema, so a schema name may not be given when creating a TEMP sequence. The sequence name must be distinct from the name of any other sequence, table, index, or view in the same schema.

Names the sequence. The name, including the implicit or explicit qualifier, must not identify a sequence or data area that already exists at the current server. If a qualified function name is specified, the schema-name cannot be QSYS2, QSYS, or SYSIBM.

For more information , please do visit source site:

http://www.sql.org/sq l-databas e/postgresql/manual/sql-create seque nce.html
Hope it will help you out.

Answered by Shobhit , an ibibo Master, at 6:47 PM on May 23, 2008

hi blogger A sequence is a database object that generates unique numbers, mostly used for primary key values. One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]
[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]
[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database. This involves creating and initializing a new single-row table with the name seqname. The generator will be owned by the user issuing the command.

Answered by laks , an ibibo Master, at 3:02 PM on May 23, 2008

A sequence is a database object that generates unique numbers, mostly used for primary key values. One can select the NEXTVAL and CURRVAL from a sequence. Selecting the NEXTVAL will automatically increment the sequence.

CREATE [ TEMPORARY | TEMP ] SEQUENCE seqname [ INCREMENT increment ]
[ MINVALUE minvalue ] [ MAXVALUE maxvalue ]
[ START start ] [ CACHE cache ] [ CYCLE ]

CREATE SEQUENCE will enter a new sequence number generator into the current database. This involves creating and initializing a new single-row table with the name seqname. The generator will be owned by the user issuing the command.

Answered by Ashish Yadav , an ibibo Wizard, at 2:48 PM on May 23, 2008

the sequence object is created only for this session, and is automatically dropped on session exit. Existing permanent sequences with the same name are not visible (in this session) while the temporary sequence exists, unless they are referenced with schema-qualified names.
seqname

The name (optionally schema-qualified) of a sequence to be created.
increment

The INCREMENT increment clause is optional. A positive value will make an ascending sequence, a negative one a descending sequence. The default value is one (1).
minvalue

The optional clause MINVALUE minvalue determines the minimum value a sequence can generate. The defaults are 1 and -2^63-1 for ascending and descending sequences, respectively.
maxvalue

The optional clause MAXVALUE maxvalue determines the maximum value for the sequence. The defaults are 2^63-1 and -1 for ascending and descending sequences, respectively.
start

The optional START start clause enables the sequence to begin anywhere. The default starting value is minvalue for ascending sequences and maxvalue for descending ones.
cache

The CACHE cache option enables sequence numbers 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.
CYCLE

The optional CYCLE keyword may be used to enable the sequence to wrap around when the maxvalue or 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. Without CYCLE, after the limit is reached nextval calls will return an error.

Answered by Om Prakash , an ibibo Master, at 2:01 PM on May 23, 2008