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4.4. Extension Metadata
You can use the extension metadata property data-ttl as a model property or on a source table to indicate a default TTL. A negative value means no TTL, 0 means do not cache, and a positive number indicates the time to live in milliseconds. If no TTL is specified on the table, then the schema will be checked. The TTL for the cache entry will be taken as the least positive value among all TTLs. Thus setting this value as a model property can quickly disable any caching against a particular source.
Here is an example that shows you how to set the property in the
vdb.xml
: