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SELECT Statements




The  SELECT statement is primarily used to retrieve zero or more  rows from one or more tables in a database.  In MySQL,  SELECT is the most commonly used DML (Data Manipulation Language) command.  In specifying a SELECT query, the user specifies a description of the desired result set.  It is built with optional clauses that specify how and what data to retrieve.  The general command syntax is shown below; 


SELECT [<clause options>] <column list> [FROM] <table> [<clause options>]; 


Basic SELECT statement example using world database (and the result data): 


mysql> SELECT Name FROM Country; 


+-------------------------------------------------+ 
| Name                                                    | 
+-------------------------------------------------+ 
| Afghanistan                                          | 
| Netherlands                                          | 
| Netherlands Antilles                            | 
| Albania                                                 | 
                 ...   
| French Southern Territories               | 
| Unites States Minor Outlying Islands | 
+-------------------------------------------------+ 


239 rows in set (#.## sec) 


The above example shows a typical query, which retrieves all the rows in a given column, from a specific table. Multiple columns can be listed in a query, as well. 
SELECT can also be used to complete arithmetic operations, like this simple addition calculation; 


mysql> SELECT 1+2; 


+-----+ 
| 1+2 | 
+-----+ 
|   3   | 
+-----+ 
1 row in set (#.## sec) 
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