Description
Specifies that the Database painter should use the ONLINE keyword when you create or drop an index on a table so that the index can be created or dropped without locking the table.
When to specify OnlineIndex
You must specify the OnlineIndex parameter before connecting to the database.
Applies to
INF Informix
Syntax
OnlineIndex='value'
|
Parameter |
Description |
|---|---|
|
value |
Specifies that the Database painter should use the ONLINE keyword when you create or drop an index. Values are:
|
Default value
OnlineIndex=0
Usage
In IDS 10.0 and later, the SQL syntax of CREATE INDEX and DROP INDEX supports the ONLINE keyword to create or drop an index in an online environment where the database and its tables are continuously available. When you use the ONLINE keyword to create or drop an index, data definition language (DDL) operations execute without applying an exclusive lock on the table on which the specified index is defined.
If you use CREATE INDEX ONLINE to create an index on a table that other users are accessing, the index is not available until no users are updating the table. If you issue DROP INDEX ONLINE to drop an index, no users can reference the index, but concurrent data manipulation language (DML) operations can use the index until the operations terminate. Dropping the index is deferred until no users are using the index.
You can set the OnlineIndex static DBParm on the System tab page in the Database Profile Setup dialog box for INF connections to specify that the Database painter should use the ONLINE keyword when you create or drop an index.
Clustered index not supported
You cannot create a clustered index using online mode because it is not supported by IDS.
Examples
To specify that the Database painter use the ONLINE keyword when you create or drop an index in the Database painter:
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Database profile
Select the Create or Drop Non-Clustered Indexes Without Dropping Tables check box on the System page in the Database Profile Setup dialog box.
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Application
Type the following in code:
SQLCA.DBParm="OnlineIndex=1"
