EMPTY_CLOB

A CLOB or NCLOB column can be initialized to a zero-length, empty CLOB or NCLOB using the EMPTY_CLOB function. Both CLOB and NCLOB data types are initialized with the EMPTY_CLOB function. This function initializes the LOB to a non-null value, so can be used for initializing any CLOB or NCLOB that has been declared as NOT NULL.

This function is not supported in TimesTen Scaleout.

SQL syntax

EMPTY_CLOB () 

Parameters

EMPTY_CLOB has no parameters.

Description

You can only use EMPTY_CLOB in the VALUES clause of an INSERT statement or the SET clause of an UPDATE statement.

Examples

The following example uses the EMPTY_CLOB function to initialize a non-null CLOB column to a zero-length value.

Command> CREATE TABLE clob_content (id NUMBER PRIMARY KEY, 
           clob_column CLOB NOT NULL ); -- Does not allow a NULL value

Command> INSERT INTO clob_content (id, clob_column) 
         VALUES (1, EMPTY_CLOB( ) );
1 row inserted.