Which Is the Not PL SQL Data Type?

When working with PL/SQL, it’s important to understand the different data types available. These data types define the kind of data that a variable can store and the operations that can be performed on that data.

In PL/SQL, we have various data types such as number, varchar2, date, boolean, and more. However, there is one type that is not considered a PL/SQL data type – clob.

The CLOB Data Type

CLOB stands for Character Large Object, and it is used to store large amounts of character data in a database column. Unlike other text-based data types such as VARCHAR2, which have a maximum size limit of 32,767 bytes, a CLOB can store up to 4 gigabytes of character data. This makes it ideal for storing large documents or text files within a database.

To declare a CLOB variable in PL/SQL, you would use the following syntax:

DECLARE
   my_clob CLOB;
BEGIN
   -- Code goes here
END;

Working with CLOBs in PL/SQL

When working with CLOBs in PL/SQL, you can perform various operations such as:

• Inserting Data: You can insert data into a CLOB column using the INSERT statement or by using the DBMS_LOB package.
• Retrieving Data: You can retrieve data from a CLOB column using the SELECT statement or by using the DBMS_LOB package.
• Updating Data: You can update data in a CLOB column using the UPDATE statement or by using the DBMS_LOB package.
• Deleting Data: You can delete data from a CLOB column using the DELETE statement.

Here’s an example that demonstrates inserting and retrieving data from a CLOB column:

DECLARE
   my_clob CLOB;
BEGIN
   -- Inserting data into the CLOB column
   INSERT INTO my_table (clob_column) VALUES ('Lorem ipsum dolor sit amet, consectetur adipiscing elit.');
   
   -- Retrieving data from the CLOB column
   SELECT clob_column INTO my_clob FROM my_table WHERE id = 1;
   
   -- Printing the retrieved data
   DBMS_OUTPUT.PUT_LINE(my_clob);
END;

Conclusion

In conclusion, while there are various data types available in PL/SQL such as number, varchar2, date, and boolean, the CLOB data type is not considered a PL/SQL-specific type. However, it is commonly used in PL/SQL to store and manipulate large amounts of character data within a database. Understanding how to work with CLOBs can be beneficial when dealing with large text-based documents or files.