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What is minus query in Oracle?
In Oracle, MINUS operator is used to return all rows in the first SELECT statement that are not returned by the second SELECT statement. Each SELECT statement has a dataset and the MINUS operator returns all documents from the first dataset and then removes all documents from the second dataset.
How do I change the view of a query in Oracle?
To redefine a view, you must use CREATE VIEW with the OR REPLACE keywords. When you issue an ALTER VIEW statement, Oracle Database recompiles the view regardless of whether it is valid or invalid. The database also invalidates any local objects that depend on the view.
What is set Serveroutput on in Oracle?
The SET SERVEROUTPUT command specifies whether output from the DBMS_OUTPUT message buffer is redirected to standard output.
Can we use order by in minus query?
3 Answers. You normally do not want results to depend on a specific column order, so I would only use this for adhoc queries. If the MINUS were replaced by UNION, the ORDER BY would apply to the result of the UNION.
How do you change the View?
To modify a view
- In Object Explorer, connect to an instance of Database Engine.
- On the Standard bar, click New Query.
- Copy and paste the following example into the query window and click Execute. The example first creates a view and then modifies the view by using ALTER VIEW.
What is set Serveroutput on size?
When the command SET SERVEROUTPUT ON executes, it calls the DBMS_OUTPUT. To increase the DBMS_OUTPUT buffer size, call DBMS_OUTPUT. ENABLE procedure with a larger buffer size after executing SET SERVER OUTPUT ON, for example: CALL DBMS_OUTPUT.
How to display SQL output back to the user?
It will not normally display results back to the user. To do this we use a procedure called dbms_output.put_line to place the results in a buffer that SQL*Plus will retrieve and display. SQL*Plus must be told to retrieve data from this buffer in order to display the results.
How does SQL Plus display PL / SQL output?
SQL*Plus must be told to retrieve data from this buffer in order to display the results. The SQL*Plus command ‘set serveroutput on’ causes SQL*Plus to retrieve and display the buffer. PL/SQL procedure successfully completed. PL/SQL procedure successfully completed.
How does SQL Plus display data from the buffer?
SQL*Plus must be told to retrieve data from this buffer in order to display the results. The SQL*Plus command ‘set serveroutput on’ causes SQL*Plus to retrieve and display the buffer.
Which is the default display width in Oracle?
When displaying CHAR, VARCHAR2 (VARCHAR), LONG, DATE, and Trusted Oracle columns, you can either accept the SQL*Plus default display width or you can change it using the COLUMN command. The sections below describe the defaults and how you can alter the defaults with the COLUMN command.