3.4.3 The Sequence Properties Dialog
The Sequence Properties Dialog is displayed when you create or edit a sequence.
To create a sequence for a selected schema, in SQL, in the Navigator tab, select Sequences from the object type drop-down list, click Object submenu , and select Create Object.
To edit a sequence for a selected schema, right-click a sequence object in the Navigator tab and select Edit.
A sequence is an object from which multiple users may generate unique integers. You can use sequences to automatically generate primary key values.
Properties pane
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Schema: Database schema in which to create the sequence.
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Name: Name of the sequence.
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Start with: Starting value of the sequence.
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Increment: Interval between successive numbers in a sequence.
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Min value: Lowest possible value for the sequence. The default is 1 for an ascending sequence and -(10^26) for a descending sequence.
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Max value: Highest possible value for the sequence. The default is 10^27 for an ascending sequence and -1 for a descending sequence.
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Cache and Cache size:
Cache
causes sequence values to be preallocated in cache, which can improve application performance; Cache size indicates the number of sequence values preallocated in cache.No Cache
causes sequence values not to be preallocated in cache. -
Cycle: Indicates whether the sequence "wraps around" to reuse numbers after reaching its maximum value (for an ascending sequence) or its minimum value (for a descending sequence). If cycling of values is not enabled, the sequence cannot generate more values after reaching its maximum or minimum value.
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Order: Indicates whether sequence numbers are generated in the order in which they are requested. If No Order is specified, sequence numbers are not guaranteed to be in the order in which they were requested.
DDL pane
You can review and save the SQL statements that are generated when creating or editing the sequence. If you want to make any changes, go back to the Properties pane and make the changes there.
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For a new sequence, click CREATE to view the generated DDL statements.
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When you edit a sequence, click UPDATE to view the generated ALTER statements. For a new sequence, the UPDATE tab will not be available.
When you are finished, click Apply.
Output pane
Displays the results of the DDL commands. If there are any errors, go to the Properties pane, fix the errors, and run the commands again. You have save to a text file or clear the output.