The following SQL statement:DELETE FROM tab1 WHERE CURRENT OF csr1 WITH RR Is used to perform which type of delete operation?
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Positioned
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Searched
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Embedded
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Dynamic
A positioned delete operation deletes the row at the current cursor position. The 'WHERE CURRENT OF csr1' clause indicates this is a positioned delete - it removes the row currently pointed to by cursor csr1. A searched delete uses a WHERE clause with conditions, an embedded delete is SQL within host code, and dynamic delete is constructed at runtime.
To answer this question, we need to understand the different types of delete operations in SQL.
A positioned delete operation is performed using a cursor, which allows you to navigate through the result set of a query and perform operations on the current row.
Let's go through each option to understand why it is correct or incorrect:
Option A) Positioned - This option is correct because the SQL statement "DELETE FROM tab1 WHERE CURRENT OF csr1 WITH RR" is a positioned delete operation. The "WHERE CURRENT OF csr1" clause indicates that the delete operation is performed on the current row of the cursor named "csr1". This type of delete operation is useful when you want to delete rows based on the current position of a cursor.
Option B) Searched - This option is incorrect because a searched delete operation is performed based on specified conditions in the WHERE clause, rather than the current position of a cursor. In a searched delete operation, you specify the conditions that must be met for a row to be deleted.
Option C) Embedded - This option is incorrect because an embedded delete operation refers to a delete statement that is embedded within a program written in a programming language (e.g., Java, C++, etc.). The given SQL statement is not embedded within any program, so it is not an embedded delete operation.
Option D) Dynamic - This option is incorrect because a dynamic delete operation refers to a delete statement that is constructed dynamically at runtime, usually based on user input or other external factors. The given SQL statement is a static statement that does not change at runtime, so it is not a dynamic delete operation.
The correct answer is A) Positioned. This option is correct because the given SQL statement performs a delete operation based on the current position of a cursor.