Differentiate between TRUNCATE and DELETE.
The Delete command will log the data changes in the log file where as the truncate will simply remove the data without it. Hence Data removed by Delete command can be rolled back but not the data removed by TRUNCATE. Truncate is a DDL statement whereas DELETE is a DML statement.

What is the maximum buffer size that can be specified using the DBMS_OUTPUT.ENABLE function?
1000000

Can you use a commit statement within a database trigger?
Yes, if you are using autonomous transactions in the Database triggers.

What is an UTL_FILE? What are different procedures and functions associated with it?
The UTL_FILE package lets your PL/SQL programs read and write operating system (OS) text files. It provides a restricted version of standard OS stream file input/output (I/O).
Subprogram -Description
FOPEN function-Opens a file for input or output with the default line size.
IS_OPEN function -Determines if a file handle refers to an open file.
FCLOSE procedure -Closes a file.
FCLOSE_ALL procedure -Closes all open file handles.
GET_LINE procedure -Reads a line of text from an open file.
PUT procedure-Writes a line to a file. This does not append a line terminator.
NEW_LINE procedure-Writes one or more OS-specific line terminators to a file.
PUT_LINE procedure -Writes a line to a file. This appends an OS-specific line terminator.
PUTF procedure -A PUT procedure with formatting.
FFLUSH procedure-Physically writes all pending output to a file.
FOPEN function -Opens a file with the maximum line size specified.

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