What is a ref cursor?

What is a ref cursor?

A ref cursor is a variable, defined as a cursor type, which will point to, or reference a cursor result. The advantage that a ref cursor has over a plain cursor is that is can be passed as a variable to a procedure or a function. The REF CURSOR can be assigned to other REF CURSOR variables.

Does ref cursor increase performance?

The next performance-related advantage of a regular cursor is also an ease-of-use feature. A regular cursor can implicitly array-fetch 100 rows at a time, whereas a ref cursor must use explicit array fetching. In other words, a regular cursor can more efficiently retrieve data by using significantly less code.

What is difference between trigger and cursor?

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A cursor is activated and thus created in response to any SQL statement. A trigger is executed in response to a DDL statement, DML statement or any database operation.

Is ref cursor static in nature?

The cursor variable can also be returned by a function and assigned to another variable. The ref cursor variable is not a cursor, but a variable that points to a cursor. These can also be dynamic, meaning that they can process dynamic SQL statements, whilst the explicit cursors are static in nature.

What is the advantage of ref cursor in Oracle?

A ref cursor is a variable, defined as a cursor type, which will point to, or reference a cursor result. The advantage that a ref cursor has over a plain cursor is that is can be passed as a variable to a procedure or a function. The ref cursor can be assigned to other ref cursor variables.

Is ref cursor can be used for dynamic queries?

Answer: Here is an example script that performs dynamic SQL and returns the data as a ref cursor. …

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Which is faster in or exists?

The EXISTS clause is much faster than IN when the subquery results is very large. Conversely, the IN clause is faster than EXISTS when the subquery results is very small. Also, the IN clause can’t compare anything with NULL values, but the EXISTS clause can compare everything with NULLs.

What is strong and weak ref cursor?

A strongly typed ref cursor always returns a known type, usually from a declared TYPE object. A weakly typed ref cursor has a return type that is dependant on the SQL statement it executes, i.e. only once the cursor is opened is the type known (at runtime).

What is cursor types of cursor and diff b W cursors?

Implicit cursors are automatically created when select statements are executed. Explicit cursors needs to be defined explicitly by the user by providing a name. They are capable of fetching a single row at a time. Explicit cursors can fetch multiple rows.

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What is difference between loop and cursor?

SQL While loop and cursor are the most common approach to repeat a statement on condition-based or determined limits. Loop and cursor can be utilized in a circumstance to deal with row-based processing in T-SQL. While SQL While loop is quicker than a cursor, reason found that cursor is defined by DECLARE CURSOR.

Can ref cursor be used for dynamic queries?

What happens when a cursor is opened?

When a cursor is opened, the following things happen: The values of the bind variables are examined. Based on the values of the bind variables, the active set (the query result) is determined. The active set pointer is set to the first row.