JDBC Driver for SQL/MX Programmer's Reference

CLOB clobTableName
For more information about using these properties, see LOB Table Name Properties.
Reserving Data Locators
A data locator is the reference pointer value (SQL LARGEINT data type) that is substituted for
the BLOB or CLOB column in the base table definition. Each object stored into the LOB table is
assigned a unique data locator value. Because the LOB table is a shared resource among all
accessors that use the particular LOB table, reserving data locators reduces contention for
getting the next value. By using a default setting of 100 reserved data locators, each JVM
instance can insert 100 large objects (not chunks) before needing a new allocation.
You can specify the number of data locators (n) to reserve for your application by using the
JDBC/MX system property jdbcmx.reserveDataLocators in the command line.
For information about specifying this property, see Setting the reserveDataLocators Property.
Storing CLOB Data
Inserting CLOB Columns by Using the Clob Interface●
Writing ASCII or Unicode Data to a CLOB Column●
Inserting CLOB Data by Using the PreparedStatement Interface●
Inserting a Clob Object by Using the setClob Method●
Inserting CLOB Columns by Using the Clob
Interface
When you insert a row containing a CLOB data type, and before the column can be updated with
real CLOB data, you can insert a row that has an "empty" CLOB value . You can insert an empty
CLOB value in a NonStop SQL/MX database by specifying EMPTY_CLOB() function for the
CLOB column in the insert statement.
The JDBC/MX driver scans the SQL string for the EMPTY_CLOB() function and substitutes
the next-available data locator.
Then, you must obtain the handle to the empty CLOB column by selecting the CLOB column for
update.
Note the limitation: Do not rename the CLOB column in the select query.