Can we use joins in cursor?

For cursors on queries that include joins, the join columns, search arguments, and select list values for the outer table in the join order are buffered with the first fetch. If more than one row is returned from the inner table in the join order, subsequent fetches use the buffered value for the outer row.

What is ref cursor in PL SQL examples?

A REF CURSOR is a PL/SQL data type whose value is the memory address of a query work area on the database. In essence, a REF CURSOR is a pointer or a handle to a result set on the database. REF CURSOR s are represented through the OracleRefCursor ODP.NET class.

How do I pass a value from one cursor to another cursor in PL SQL?

1 Answer. It is possible to reference another cursor within the first one: declare cursor c1 is select distinct Assigned from table_name; cursor c2(p_Assigned in varchar2) is select id, Assigned from table_name where Assigned = p_Assigned; begin for r1 in c1 loop dbms_output.

Do cursors lock tables?

Why cursors are slow To populate a cursor, database tables are iterated on row-by-row basis rather than in sets. While a cursor is being populated, the table being iterated is locked. While the cursor is open, a table cannot be accessed or updated by the other users. This makes cursor-based operations extremely.

What is alternative of cursor in SQL Server?

In this article, I am explaining how you can use cursor alternatives like as WHILE loop, Temporary tables and Table variables. We should use cursor in that case when there is no option except cursor.

What can we use instead of cursor in SQL?

Temporary tables have been in use for a long time and provide an excellent way to replace cursors for large data sets. Just like table variables, temporary tables can hold the result set so that we can perform the necessary operations by processing it with an iterating algorithm such as a ‘while’ loop.

How do I pass one cursor to another cursor?

The trick to declaring a cursor within a cursor is that you need to continue to open and close the second cursor each time a new record is retrieved from the first cursor. That way, the second cursor will use the new variable values from the first cursor.

What can I use instead of cursor in SQL?

SQL Server Alternatives Cursor

Using Cursor.
Using Table Variable.
Using Temporary Table.

What is replacement of cursor in SQL Server?

Alternative 2: Temporary Tables We can also use temporary tables instead of SQL cursors to iterate the result set one row at a time. Temporary tables have been in use for a long time and provide an excellent way to replace cursors for large data sets.

What are the types of REF CURSOR in PL / SQL?

PL/SQL has two forms of REF CURSOR typeS: strong typed and weak typed REF CURSOR. The following shows an example of a strong REF CURSOR. DECLARE TYPE customer_t IS REF CURSOR RETURN customers%ROWTYPE; c_customer customer_t;

How is a cursor variable declared in PL / SQL?

With a cursor variable, you simply pass the reference to that cursor. To declare a cursor variable, you use the REF CURSOR is the data type. PL/SQL has two forms of REF CURSOR typeS: strong typed and weak typed REF CURSOR.

Can a strongly typed cursor be defined in SQL?

A strongly typed cursor type is less flexible but less prone to programming errors. The PL/SQL compiler will verify that the FETCH clause has the correct variable/record for the cursor return type at compile time. Once the cursor type is defined, the actual variable can be defined as the cursor type.

Which is the best definition of 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.

Can we use joins in cursor?