General Interview Questions on PL/SQL

• What is the purpose of the PL/SQL language?
• Say True or False. If False, explain why.
• Routines written in PL/SQL can be called in Oracle call interface, Java, Pro*C/C++, COBOL etc. 
• Say True or False. If False, explain why.
• PL/SQL does not have data types or variables.
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• State few notable characteristics of PL/SQL.
• Name few schema objects that can be created using PL/SQL?
• State some features or programming constructs supported by PL/SQL.
• What are the three basic sections of a PL/SQL block?
• What is wrong in the following assignment statement?
• balance = balance + 2000;
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• Write a single statement that concatenates the words ‘Hello’ and ‘World’ and assign it in a variable named greeting.
• Which operator has the highest precedence among the following −
• AND, NOT, OR?
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• Which of the following operator has the lowest precedence among the following −
• **, OR, NULL ?
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• What does the colon sign (: ) implies in the following statement?
• :deficit := balance – loan;
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• What is the purpose of %type data type? Explain with example.
• What is the purpose of %rowtype data type? Explain with example.
• What is a PL/SQL package?
• What is a trigger?
• What are the PL/SQL cursors?
• Say True or False. If False, explain why.
• PL/SQL engine is part of Oracle Server.
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• Say True or False. If False, explain why.
• The BEGIN declaration starts the variable declaration sections of a PL/SQL block.
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• Say True or False. If False, explain why.
• The PL/SQL engine executes the procedural commands and passes the SQL commands for the Oracle server to process.
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• Say True or False. If False, explain why.
• PL/SQL supports the CREATE command.
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• What is returned by the cursor attribute SQL%ROWCOUNT?
• What is returned by the cursor attribute SQL%FOUND?
• What is returned by the cursor attribute SQL%NOTFOUND?
• Which command/commands allow iteration a use of loops in a PL/SQL block?
• What is the difference in execution of triggers and stored procedures?
• What are the uses of triggers?
• Say True or False. If False, explain why.
• Triggers can be associated to a view.
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• Say True or False. If False, explain why.
• When a trigger is associated to a view, the base table triggers are normally disabled.
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• Say True or False. If False, explain why.
• A trigger can perform the role of a constraint, forcing an integrity rule.
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• Say True or False. If False, explain why.
• A trigger can execute the COMMIT, ROLLBACK, or SAVEPOINT commands.
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• What is the use of a WHEN clause in a trigger?
• Say True or False. If False, explain why.
• Statement level triggers are triggered only once.
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• What is the purpose of the optional argument [OR REPLACE] in a CREATE TRIGGER command?
• Say True or False. If False, explain why.
• INSTEAD OF is a valid option only for triggers in a table.
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• Write a statement to disable a trigger named update_marks.
• Which command is used to delete a trigger?
• Which command is used to delete a procedure?
• What is the difference between a function and a stored procedure?
• How do you declare a user-defined exception?
• What do you understand by explicit cursors?
• What are the steps that need to be performed to use an explicit cursor? Discuss briefly.
• PL/SQL packages usually have two parts. What are these two parts?
• Which command(s) are used for creating PL/SQL packages?
• How do you refer to the types, objects and subprograms declared within a package?
• Say True or False. If False, explain why.
• PL/SQL allows subprogram overloading feature within a package.
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• Which command is used to delete a package?
• What is the difference between implicit and explicit cursors?
• Say True or False. If False, explain why.
• The %NOTFOUND attribute returns true when the cursor is not created explicitly.
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• Say True or False. If False, explain why.
• The %ROWCOUNT attribute returns the total number of rows returned by the FETCH command.