Is ref cursor PL SQL Oracle?

Is ref cursor Plsql?

Ref Cursor is an acronym of Reference to a Cursor. It is a PL/SQL datatype using which you can declare a special type of variable called Cursor Variable.

What is the difference between cursor and ref cursor in Oracle?

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.

What is ref type in PL SQL?

A ref is a pointer to a record in a SQL (i.e. database) object table. Consequently Oracle supports them in SQL but not in PL/SQL.

How do I display ref cursor output in PL SQL Developer?

Using the PRINT command in a SQL Worksheet

Using the classic SQL*PLUS PRINT command to view the refcursor output will work in SQL Developer just like it would work in your command line tools. You execute your program, you create a local variable or 3 to ‘catch’ said output, and then you PRINT it.

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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.

What is the difference between ref cursor and Sys_refcursor?

There is no difference between using a type declared as REF CURSOR and using SYS_REFCURSOR , because SYS_REFCURSOR is defined in the STANDARD package as a REF CURSOR in the same way that we declared the type ref_cursor . … type sys_refcursor is ref cursor; SYS_REFCURSOR was introduced in Oracle 9i.

What is a cursor in Oracle SQL?

Cursors are used when the user needs to update records in a singleton fashion or in a row by row manner, in a database table. The Data that is stored in the Cursor is called the Active Data Set. Oracle DBMS has another predefined area in the main memory Set, within which the cursors are opened.

What is collection in Oracle PL SQL?

A collection is an ordered group of elements having the same data type. Each element is identified by a unique subscript that represents its position in the collection. PL/SQL provides three collection types − Index-by tables or Associative array. Nested table.

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 cursor variable in Oracle PL SQL?

A cursor variable is a cursor that contains a pointer to a query result set. The result set is determined by execution of the OPEN FOR statement using the cursor variable. The same cursor variable can be opened a number of times with separate OPEN FOR statements containing different queries. …

What is ref in SQL?

To use a reference type in an SQL statement, use REF(t ype-name ), where type-name represents the referenced type. … Db2 uses the reference type as the type of the object identifier column in typed tables. The object identifier uniquely identifies a row object in the typed table hierarchy.

What is strong ref cursor in Oracle?

A ref cursor which has fixed return type is called a Strong Ref Cursor in Oracle Database. Because of fixed return type, strong ref cursors can only be used selectively. For instance with those SELECT statements that return the result whose datatype matches with the one that you have fixed during cursor’s declaration.

What is set Serveroutput on?

Basically the use of SET SERVEROUTPUT is to display the query answer in SQL *PLUS interface… When you use the DBMS_OUTPUT. PUT_LINE procedure, the procedure will write the passing string into the Oracle buffer. … Use the “Set serveroutput on” to display the buffer used by dbms_output.

How do I view the output variables in SQL Developer?

How to Turn Output On in SQL Developer

  1. Open Oracle Developer.
  2. Click “View” and then click “Dbms Output.”
  3. Click the green “+” sign in the window that opens and select the database connection from which you want output. Output will now appear for that database in a new tab.
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What is ref CURSOR in PostgreSQL?

Declaring cursors

PostgreSQL provides you with a special type called REFCURSOR to declare a cursor variable. … Then, you put the CURSOR keyword followed by a list of comma-separated arguments ( name datatype ) that defines parameters for the query. These arguments will be substituted by values when the cursor is opened.

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