Explanation:
You cannot specify column names in the DELETE clause of the DELETE statement. Syntax of this command is: DELETE FROM table_name WHERE column_name = value.
Incorrect Answers:
1: Error in this statement is related with list of columns in the DELETE statement, not with absence of row with DEPT_ID = 90 in the EMPLOYEES table.
2: Error in this statement is related with list of columns in the DELETE statement, not with NOT NULL constraint on the JOB_ID column.
4: Error in this statement is related with list of columns in the DELETE statement, not with the primary key constraint on the EMPLOYEE_ID column.
OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 270-273
Chapter 6: Manipulating Oracle Data

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