| What is SQL? SQL stands for Structured
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| | table data3. Manipulate the table dataSQL
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| Query Language and is the lingua franca
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| | is predominantly used by 2 types of users
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| in the database world. SQL is a standard
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| | - programs and humans (keying in the
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| that is used by all database vendors and
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| | commands through a database client) - to
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| programmers to define, extract and access
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| | pass instructions to databases. SQL
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| the information that is stored in
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| | commands can be keyed into a database
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| databases. SQL began life as an IBM
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| | client like the MySQL Query Browser or
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| creation but was standardized by the
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| | the SQL Server Enterprise Manager and
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| American National Standards Institute
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| | executed to either return a result or
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| (ANSI) and the International
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| | modify records in the database. SQL can
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| Organization for Standardization (ISO) as
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| | also be used in conjunction with
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| ANSI/ISO SQL in 1988. Since then ANSI/ISO
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| | programming language or scripting
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| SQL standard continued to evolve. The
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| | language like Microsoft Visual Basic or
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| ANSI-SQL group has since published three
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| | PHP to communicate with the
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| standards over the years:1. SQL89
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| | database.Although SQL is a world
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| (SQL1)2. SQL92 (SQL2)3. SQL99 (SQL3)SQL
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| | standard, it is unfortunate that most
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| is a query language. It is English-like
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| | database vendors have come up with
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| and easy to use. However, although there
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| | different dialects and variations. This
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| are more than 90 SQL reserved words,
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| | is because every database vendor wants to
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| most programmers seldom use more than the
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| | differentiate their database products
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| following handful of commands - SELECT,
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| | from the crowd. One good example is
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| INSERT, UPDATE, DELETE, FROM, WHERE,
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| | Microsoft SQL Server's TRANSACT-SQL.
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| HAVING, BETWEEN, LIKE, OR, AND, NOT, IN,
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| | TRANSACT-SQL is a superset of SQL and is
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| ORDER, GROUP and BY.For example, if you
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| | designed for use only with Microsoft SQL
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| had a database table named "employees"
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| | Server. Although it does make programming
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| and you wanted to retrieve all records
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| | much easier for software developers, it
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| where the employee has the last name
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| | is not compliant with other databases
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| "goodman", you would use the following
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| | like Oracle or MySQL - making
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| SQL statement:SELECT * FROM employees
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| | TRANSACT-SQL programs non
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| WHERE lastname = 'goodman';There are many
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| | database-portable. As such, although many
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| different categories of SQL statements
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| | of these features are powerful and
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| but the basic ones which all programmers
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| | robust, it is good practice to exercise
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| should be familiar with are the SQL
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| | caution and limit your SQL use to be
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| statements that:1. Create tables and
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| | compliant with the ANSI/ISO SQL
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| manipulate their definitions2. Query the
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| | standards and ODBC-Compliant.
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