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- Use of Index - The EXPLAIN keyword - analyze the execution of a query. - Avoid calculation on a field. e.g., use "rate - MySQL uses l...

The root of postgresql is called 'postgres'. See details below: Change forgotten PostgreSQL password Some common postgresql comm...

Bubblemark animation test : Silverlight (JavaScript and CLR) vs DHTML vs Flash (Flex) vs WPF vs Apollo vs Java (Swing)

Upon startup, a computer running windows XP is dead with a blue screen reporting "UNMOUNTABLE_BOOT_VOLUME" error. The reason is th...

A primary key is usually a unique clustered index. A primary key cannot be null. A unique clustered index, if not a primary key, can be null...

Sometimes, for example, when you add a column to a table, or when you want to create a primary key field on a table containing millions of r...

When a query goes complicated and data involved is huge, query plan reveals the query execution sequence and helps to optimize the query [1]...