7. Further SQL
The syllabus is mainly concerned with the fundamental sql queries of CREATE, INSERT, UPDATE, SELECT and DELETE
And the examples demonstrate their use with a single table.
But a full relational database is usually comprised of several related tables. SQL supports the extraction of records based on the values across more than one table.
A key command is the JOIN. This allows records selection, insertion and updates to occur based on criteria across a number of tables. If you wish to find out more about sql then we recommend you explore the uses of this command as well
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: SQL JOIN command
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