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SQL Facts SQL stands for Structured Query Language SQL is pronounced “sequel” SQL is declarative language SQL is used to access & manipulate data in databases Top SQL DBs are MS SQL Server, Oracle, DB2, and MySQL Database Definitions RDBMS (Relational Database Management System) – Software that stores and manipulates data arranged in relational database tables. Table – A set of data arranged in columns and rows. The columns represent characteristics of stored data and the rows represent actual data entries. How to select data from a table

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SQL Commands Categories Data Query Language (DQL) x SELECT - Retrieve data from table(s) Data Manipulation Language (DML) x INSERT - Insert data into db table x UPDATE - Update data in db table x DELETE - Delete data from table Data Definition Language (DDL) x CREATE - Create db object (table, view, etc.) x ALTER - Modify db object (table, view, etc.) x DROP - Delete db object (table, view, etc.) Data Control Language (DCL) x GRANT - Assign privilege x REVOKE - remove privilege How to insert data in a table INSERT INTO () VALUES () Example: INSERT INTO Orders (FirstName, LastName, OrderDate) VALUES ('John', 'Smith', '10/10/2010') How to delete data from a table DELETE FROM WHERE Example: DELETE FROM Orders WHERE OrderDate < '10/10/2010'

SELECT FROM WHERE Example: SELECT FirstName, LastName, OrderDate FROM Orders WHERE OrderDate > '10/10/2010' How to update data in a table UPDATE SET = , = , … WHERE Example: UPDATE Orders SET FirstName = 'John', LastName = 'Who' WHERE LastName='Wo' How to group data and use aggregates SELECT , () FROM WHERE GROUP BY Example: SELECT LastName, SUM(OrderValue) FROM Orders WHERE OrderDate > '10/10/2010' GROUP BY LastName How to select data from more than one table SELECT FROM JOIN ON . = . Example: SELECT Orders.LastName, Countries.CountryName FROM Orders JOIN