NOCOPY is a hint to the PL/SQL compiler to pass OUT and IN OUT parameters by reference instead of by value. The use of NOCOPY saves on the processing and memory overhead of copying data from subprogram to calling program.

What is Nocopy in Oracle procedure?

NOCOPY is a hint to the PL/SQL compiler to pass OUT and IN OUT parameters by reference instead of by value. The use of NOCOPY saves on the processing and memory overhead of copying data from subprogram to calling program.

What is call by value and call by reference in Oracle?

call by value: a copy of the parameter is passed into the procedure, which gets copied back when the procedure completes (IN OUT and OUT parameters) call by reference: IN parameters. with the NOCOPY hint you can have IN OUT and OUT parameters behave as call by reference parameters.

What is ref cursor in Oracle with example?

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.

What are the three parameter modes for procedures?

The three parameter modes, IN (the default), OUT , and IN OUT , can be used with any subprogram. However, avoid using the OUT and IN OUT modes with functions. The purpose of a function is to take no arguments and return a single value.

When a parameter to the procedure is passes using Nocopy option the modification done to the formal parameter is reflected in actual parameter?

When a parameter is passed by reference, the formal and actual parameters refer to the same memory location. Any changes to the value of the formal parameter are immediately reflected in the actual parameter as well. Aliasing is not an issue for IN parameters, because subprograms cannot assign values to them.

What is call by value with example?

The call by value method of passing arguments to a function copies the actual value of an argument into the formal parameter of the function. In this case, changes made to the parameter inside the function have no effect on the argument. By default, C programming uses call by value to pass arguments.

What is Materialised views in Oracle?

A materialized view is a database object that contains the results of a query. The FROM clause of the query can name tables, views, and other materialized views. Collectively these objects are called master tables (a replication term) or detail tables (a data warehousing term).

What is difference between cursor and ref 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.

How many types of collections are there in Oracle?

three collection types
PL/SQL has three collection types—associative array, VARRAY (variable-size array), and nested table.