SQL
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1986 – IBM developed the first prototype of relational database and standardized
by ANSI. The first relational database was released by Relational Software which
later came to be known as Oracle.
SQL Process
When you are executing an SQL command for any RDBMS, the system determines the
best way to carry out your request and SQL engine figures out how to interpret the task.
There are various components included in this process.
These components are –
Query Dispatcher
Optimization Engines
Classic Query Engine
SQL Query Engine, etc.
A classic query engine handles all the non-SQL queries, but a SQL query engine won't
handle logical files.
Following is a simple diagram showing the SQL Architecture:
SQL
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SQL Commands
The standard SQL commands to interact with relational databases are CREATE, SELECT,
INSERT, UPDATE, DELETE and DROP. These commands can be classified into the following
groups based on their nature:
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