LAMP & Oracle Technical Information

The extract() function converts elements in an array into variables in their own right, an act commonly called "exporting"
in other languages. Extract takes a minimum of one parameter, an array, and returns the number of elements extracted.
The following example is useful for retriving information from database.

Example:

SHOW statement display status information and variables from the server. You can reduce the number
of variables shown with the LIKE clause, based on a naming pattern for the variable name.
Similarly, the WHERE clause may be used to refine the results set. The following is an example
of how you can use this statement with the LIKE clause.

SQL Condition Clauses:

field = value
field > value
field >= value
filed != value (field is not equal to value)
field <> value (field is not equal to value)
field BETWEEN value1 and value2
field LIKE value
field NOT LIKE vale
field is NULL
field IN (value1, value2, value3, value4)
field NOT IN (value1, value2, value3)

Selecting from Multiple table:

ROLLBACK TO SAVEPOINT identifier