JDBC Type 4 Driver 2.0 Programmer's Reference (SQL/MX 2.x)

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Backing Up and Restoring LOB Columns
For basic information about backing up and restoring databases, see the SQL/MX Installation and Management Manual.
That discussion describes the special considerations you must take for backing up and restoring tables that have LOB
columns implemented for the Type 4 driver (because both base tables and LOB tables are involved).
When backing up and restoring a base table, make sure that the name of the table is unchanged. LOB data is not be
accessible after restoration if the base table name has changed.
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Triggers cannot be restored by using Backup and Restore 2.0. You can capture the DDL for the CREATE
statements executed for these objects and use this information to manually recreate these objects after a Restore
operation.
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Make sure that the time interval in the backup of the base tables and LOB tables is not large. A smaller time interval
ensures that the data referred to by the base table is present in the LOB table.
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Limitations of LOB Data (CLOB and BLOB Data Types)
Limitations of the CLOB and BLOB data types, collectively referred to as LOB data, are:
LOB columns can only be in the target column list of these SQL statements:
INSERT statement
❍
Select list of a SELECT statement❍
Column name in the SET clause of an UPDATE statement❍
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LOB columns cannot be referenced in the SQL/MX functions and expressions.●
LOB data is not deleted from the LOB table when the base row is deleted unless a trigger is established. For
information about triggers, see Using SQL/MX Triggers to Delete LOB Data.
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LOB data is not accessible if the base table name is changed.●
LOB columns cannot be copied to another table by using the SQL/MX utility commands.●
The name of a base table that has CLOB or BLOB columns must be unique across all catalogs and schemas when
more than one of these base tables share a single LOB table.
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Note: Adding a trigger can affect up to three schemas. For each schema, you must either own the schema or be the
super ID.
The schema where the trigger is created.●
The schema where the subject table (LOB table) exists.●
The schema where the referenced table (base table) exists.●
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Chapter 5. Working with BLOB and
CLOB Data
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