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SQL is a standard language for accessing and manipulating databases.
What is SQL?
SQL stands for Structured Query Language
SQL lets you access and manipulate databases
SQL is an ANSI (American National Standards Institute) standard
What Can SQL do?
SQL can execute queries against a database
SQL can retrieve data from a database
SQL can insert records in a database
SQL can update records in a database
SQL can delete records from a database
SQL can create new databases
SQL can create new tables in a database
SQL can create stored procedures in a database
SQL can create views in a database
SQL can set permissions on tables, procedures, and views
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A database most often contains one or more tables. Each table is identified by a name (e.g. "Customers" or "Orders"). Tables contain records (rows) with data.
Below is an example of a table called "Persons":
|P_Id |LastName |FirstName |Address |City |
|1 |Hansen |Ola |Timoteivn 10 |Sandnes |
|2 |Svendson |Tove |Borgvn 23 |Sandnes |
|3 |Pettersen |Kari |Storgt 20 |Stavanger |
The table above contains three records (one for each person)