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In addition to static SQL discussed in this chapter, PL/SQL also supports dynamic SQL, which enables you to execute SQL data definition, data control, and session control statements dynamically.

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Implicit cursor is used for all other SQL statements (INSERT, UPDATE, DELETE, and single-row SELECT…INTO) • Actually PL/SQL engine takes care of the above four steps automatically) Drawbacks of Implicit Cursors • It is less efficient than an explicit cursor -- it performs minimum two fetches to see if it has more than one rows. However, there is no explicit cursor for UPDATE, DELETE, and INSERT statements.

is not declared SELECT * FROM employee; -- this is a static cursor • SELECT statement contains no INTO clause.

Here ‘emp_tbl’ in the table which contains records of all the employees. On every fetch statement, the pointer moves to the next row.

2) Accessing the records in the cursor: Once the cursor is created in the declaration section we can access the cursor in the execution section of the PL/SQL program. If you want to fetch after the last row, the program will throw an error.

When there is more than one row in a cursor we can use loops along with explicit cursor attributes to fetch all the records.

Points to remember while fetching a row: · We can fetch the rows in a cursor to a PL/SQL Record or a list of variables created in the PL/SQL Block.

• Cursor is a handle (or pointer), to the context area.

PL/SQL program can control the context area using Cursor. • SELECT statement should return only one row at a time in previous PL/SQL programs. • We use the idea of Cursor to handle the above problem. Even if your query returns only a single row, you might still decide to use an explicit cursor.

You can manipulate Oracle data flexibly and safely because PL/SQL fully supports all SQL data manipulation statements (except ), transaction control statements, functions, pseudocolumns, and operators.

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