Defining a Table with Row Expiration

When defining a table, you can set the default_ttl property to a non-zero value to enable row expiration. The time interval is specified in seconds. Unless a different TTL was set on a particular row, rows inserted in a table inherit the default TTL value set on the table and expires after their TTL interval has elapsed. If the default_ttl property is not set or is set to 0 (zero), the rows of the table never expire and row expiration is not enabled for the table.

    Procedure
  1. Open the command prompt, and run tibdg using the following syntax to create a table in which rows expire:
    table create [default_ttl=<time interval in seconds>] table_name key_column_name key_column_type
    For example, if rows expire after 1 hour, the table would be created with the following tibdg command:
    tibdg table create default_ttl=3600 t1 key long value string
    For the same example, you can use the following SQL DDL command:
    CREATE TABLE t1 (key INT PRIMARY KEY, value VARCHAR) default_ttl=3600
    Note: To ensure that a table is scanned for expired rows periodically, use the option expiration_scan_period. The default value is 3600 seconds and the minimum value is 1 second.
ResultAll rows in the table expire after the specified TTL.

If you are using the C or Java APIs for ActiveSpaces, you can override the TTL for a table by setting the TTL property at a row level. For more details, see Overriding the Default TTL for a Single Row.