What is difference between ref cursor and cursor?

What is difference between ref cursor and cursor?

A cursor is really any SQL statement that runs DML (select, insert, update, delete) on your database. A ref cursor is a pointer to a result set. This is normally used to open a query on the database server, then leave it up to the client to fetch the result it needs.

Why ref cursor is used in PL SQL?

Using REF CURSOR s is one of the most powerful, flexible, and scalable ways to return query results from an Oracle Database to a client application. A REF CURSOR is a PL/SQL data type whose value is the memory address of a query work area on the database.

Is ref cursor static in nature?

The Ref-Cursors does not pass the entire result set in a huge sack, rather it just hands over the reference of that cursor to the calling program, thus making it more performance friendly. These can also be dynamic, meaning that they can process dynamic SQL statements, whilst the explicit cursors are static in nature.

What is the difference between varchar and VARCHAR2?

The main difference is that VARCHAR is ANSI Standard and VARCHAR2 is Oracle standard. The VarChar2 data type is used to store the character values. It is a variable-length data type i.e we can change the size of the character variable at execution time. Hence, it is also called a Dynamic datatype.

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 bulk collection in Oracle PL SQL?

A bulk collect is a method of fetching data where the PL/SQL engine tells the SQL engine to collect many rows at once and place them in a collection. The SQL engine retrieves all the rows and loads them into the collection and switches back to the PL/SQL engine. All the rows are retrieved with only 2 context switches.

What is difference between %type and %row type?

%TYPE : Used to declare a field with the same type as that of a specified table’s column. %ROWTYPE: Used to declare a record with the same types as found in the specified table, view or cursor (= multiple columns).