Technical data

DDL operations on cached Oracle tables may cause cache group operations to fail
Troubleshooting Oracle In-Memory Database Cache 4-9
Unsupported data type mapping
When you try to create a cache group, you may receive the following error:
5115: Unsupported type mapping for column name
For example, table tab on Oracle can be described as follows:
COL1 NUMBER(38) NOT NULL
COL2 NUMBER(38)
Try to create the cache group as follows:
CREATE CACHE GROUP cg FROM tab(col1 CHAR(10) NOT NULL PRIMARY KEY);
Error 5119 is displayed and the cache group is not created because the statement
attempts to map a column of NUMBER data type to a column of CHAR data type.
See "Data type mappings allowed for key columns" in the Oracle In-Memory Database
Cache User's Guide.
Null constraint does not match Oracle
When you try to create a cache group, you may receive the following warning:
Warning 5119: Column name has different nullability setting in Oracle
For example, table tab on Oracle can be described as follows:
COL1 NUMBER(38) NOT NULL
COL2 NUMBER(38)
Try to create the cache group as follows:
CREATE CACHE GROUP cg
FROM tab(col1 INTEGER NOT NULL PRIMARY KEY, col2 INTEGER NOT NULL);
Warning 5119 is displayed because col2 on Oracle does not have a NULL constraint,
but col2 in the cache group is defined as NOT NULL.
DDL operations on cached Oracle tables may cause cache group
operations to fail
DDL operations that are performed on an Oracle table that is being cached in
TimesTen may cause a failure on the cache group. For example, the user drops a
column on the Oracle table that is being cached in TimesTen. When the cache group is
propagated or flushed, TimesTen will update the column that no longer exists in the
Oracle table. When the cache group loads or refreshes, then TimesTen attempts to
retrieve data from the column that has been dropped.
The following cache group operations may fail:
■ Autorefresh does not occur.
■ AWT cache group operations are not propagated or refreshed to/from Oracle.
■ Cache group load or propagate fails.
If you suspect the cache group operations are not working properly because of a DDL
operation on the Oracle base table, then use DDL tracking to diagnose the issue. DDL
tracking saves the change history for all the cached Oracle tables. The SQL statement