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Select (SQL)

A SELECT statement in SQL returns a result set of records from one of more tables.

Examples

Table "T"	Query	Result
C1 C2 1 a 2 b	SELECT * FROM T;	C1 C2 1 a 2 b
C1 C2 1 a 2 b	SELECT C1 FROM T;	C1 1 2
C1 C2 1 a 2 b	SELECT * FROM T WHERE C1 = 1;	C1 C2 1 a

Given a table T, the query SELECT * FROM T; will result in all the elements of all the rows of the table being shown.

With the same table, the query SELECT C1 FROM T; will result in the elements from the column C1 of all the rows of the table being shown — in Relational algebra terms, a projection will be performed.

With the same table, the query SELECT * FROM T WHERE C1 = 1; will result in all the elements of all the rows where the value of column C1 is '1' being shown — in Relational algebra terms, a selection will be performed, because of the WHERE keyword.

See also:

• JOIN keyword