ORATraining Blog

Tweet Oracle PL/SQL Quick Reference   PL/SQL Block Structure DECLARE –Optional   –Variables, Cursors, User-defined exceptions BEGIN –Mandatory   –SQL statements   –PL/SQL statements EXCEPTION –Optional   –Actions to perform when errors occur END; –Mandatory

Tweet Oracle SQL Quick Reference SELECT Query Statement SELECT [DISTINCT] {*, column [alias],…} FROM table WHERE condition(s)] ORDER BY {column, exp, alias} [ASC|DESC]] NOTE: Avoid using DISTINCT with large table as it first does sorting of all the rows and then eliminates duplicate rows, so need a full table scan and thus it’s very slow. [...]

Tweet Oracle SQL Tuning Tips consideration when writing an SQL statement is that it returns a correct result. The second is that it be the most efficient for a given situation.  You can use many different SQL statements to achieve the same result. It is often the case that only one statement will be the [...]

Tweet Using SQL*Plus SQL*Plus is a command-line tool that provides access to the Oracle RDBMS. SQL*Plus enables you to: Enter SQL*Plus commands to configure the SQL*Plus environment Startup and shutdown an Oracle database Connect to an Oracle database Enter and execute SQL commands and PL/SQL blocks Format and print query results SQL*Plus is available on [...]

Tweet Oracle Data Export and Import utility The Import and Export utilities work together; Export sends database definitions and actual data to an export file and Import can read the file to perform many different tasks. You can use Export and Import for many important database tasks, such as restoring a table, generating CREATE scripts, [...]