1. Cache Guide
  2. Methods for Transmitting Changes Between TimesTen and Oracle Databases
  3. Setting a Passthrough Level
  4. PassThrough=1

PassThrough=1

PassThrough=1 specifies that all DDL are run on TimesTen and most SQL statements are run on TimesTen unless the tables referenced only exist on the Oracle database or the SQL statement can only be parsed or understood on the Oracle database.

Set PassThrough=1 to specify that:

  • DDL statements are always executed on TimesTen.

  • INSERT, UPDATE and DELETE statements are run on TimesTen unless they reference one or more tables that do not exist in TimesTen. If they reference one or more tables that do not exist in TimesTen, then these statements are passed through to run on the Oracle database.

  • If SQL statements generate a syntax error in TimesTen, include keywords that do not exist in TimesTen SQL, or if one or more tables referenced within the statement do not exist in TimesTen, then these statements are passed through to run on the Oracle database.

  • If TimesTen cannot parse INSERT, UPDATE or DELETE statements, TimesTen returns an error and the statement is not passed through to the Oracle database.

Figure 5-2 shows that Table A is updated in the TimesTen database, while Table G is updated in the Oracle database because Table G does not exist in the TimesTen database.

Figure 5-2 PassThrough=1

Description of Figure 5-2 follows
Description of "Figure 5-2 PassThrough=1"