Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

Oracle9i offers some great tools to make it easy to view the execution plan and trace information for a SQL statement. Prior to Oracle8i, you had to create a plan table and execute special syntax to ...

To update the data, you can specify view descriptors in the PROC SQL DELETE, INSERT, and UPDATE statements. You must have access to the data through appropriate ADABAS and/or NATURAL security options ...

The Oracle SQL*Plus product has introduced some new features that have long been missing from this utility program, and some to support the new features. Here's a rundown of the new features in Oracle ...

Inside a relational database management system, the princi­pal persisted data structure is considered a logical relation. Operations performed against that data within the RDBMS result in a logical ...

The SQL query language was designed to provide programmers with a way to create, maintain and modify databases in a structured way. Using SQL, the programmer can add and remove items from databases as ...

specifies the query that you are sending to the DBMS. The query can use any DBMS-specific SQL statement or syntax that is valid for the DBMS. However, the query cannot contain a semicolon because to ...

Assuring optimal performance of database applications starts with coding properly formulated SQL. Poorly written SQL and application code is the cause of most performance problems. As much as 75% of ...