Select statement in sql language

SQL SELECT statement

The SELECT statement is used to select data from the database.

The results are stored in a result table, called a result set.

SQL SELECT syntax

SELECT column_name,column_name
FROM table_name;

and:

SELECT * FROM table_name;

Note: SQL statements are not case-sensitive. SELECT is equivalent to select.

SQL SELECT Example

To get the contents of the columns named "LastName" and "FirstName" (from the database table named "Persons"), please Use a SELECT statement like this:

SELECT LastName,FirstName FROM Persons

"Persons" table:

##IdLastNameFirstNameAddressCity1AdamsJohnOxford StreetLondon2BushGeorgeFifth AvenueNew York3CarterThomasChangan StreetBeijing Result:

LastNameFirstNameAdamsJohnBushGeorge##Carter

Thomas

SQL SELECT * Example

Now we want to select all columns from the "Persons" table.

Please use the symbol * instead of column names, like this:

SELECT * FROM Persons

Tip: The asterisk (*) is a shortcut to select all columns.

Result:

##IdLastNameFirstName AddressCity1AdamsJohnOxford StreetLondon2BushGeorgeFifth AvenueNew York3CarterThomasChangan StreetBeijing

Navigating in the result-set

The results obtained by the SQL query program are stored in a result set. Most database software systems allow the use of programmatic functions to navigate within result sets, such as: Move-To-First-Record, Get-Record-Content, Move-To-Next-Record, and so on.

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