ITC Plsql Developer Interview Questions and Answers

VARCHAR can store up to 2000 bytes while VARCHAR2 can store up to 4000 bytes.

• VARCHAR can store variable-length character strings up to 2000 bytes.

• VARCHAR2 can store variable-length character strings up to 4000 bytes.

• VARCHAR will occupy space for NULL values while VARCHAR2 will not.

• VARCHAR2 is more efficient in terms of storage and performance compared to VARCHAR.

Composite indexes are indexes that are created on multiple columns in a database table.

• Composite indexes improve query performance for queries that involve multiple columns

• They can be created using the CREATE INDEX statement in SQL

• Example: CREATE INDEX idx_name ON table_name (column1, column2)