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11
Compatibility Between TimesTen and Oracle
11
This chapter lists compatibility issues between TimesTen and Oracle. The list is not
complete, but it indicates areas that require special attention. It includes the following
topics:
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Summary of compatibility issues
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Transaction semantics
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API compatibility
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SQL compatibility
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Mappings between Oracle and TimesTen data types
Summary of compatibility issues
Consider the following differences between TimesTen and Oracle:
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TimesTen and Oracle database metadata are stored differently. See "API
compatibility" on page 11-2 for more information.
TimesTen and Oracle have different transaction isolation models. See "Transaction
semantics" on page 11-1 for more information.
TimesTen and Oracle have different connection and statement properties. For
example, TimesTen does not support catalog names, scrollable cursors or
updateable cursors.
Sequences are not cached and synchronized between the TimesTen database and
the corresponding Oracle database. See "SQL expressions" on page 11-5 for more
information.
Side effects of Oracle triggers and stored procedures are not reflected in the
TimesTen database until after an automatic or manual refresh operation.
Transaction semantics
TimesTen and Oracle transaction semantics differ as follows:
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Oracle serializable transactions can fail at commit time because the transaction
cannot be serialized. TimesTen uses locking to enforce serializability.
Oracle users can lock tables explicitly through SQL. This locking feature is not
supported in TimesTen.
Oracle supports savepoints while TimesTen does not.
Compatibility Between TimesTen and Oracle 11-1