UNLOAD statement
Use the UNLOAD statement to write the rows retrieved by a SELECT statement to an operating-system file. The UNLOAD statement is an extension to the ANSI/ISO standard for SQL.
Only DB-Access supports the UNLOAD statement.
SyntaxElement | Description | Restrictions | Syntax |
---|---|---|---|
delimiter | Quoted string to specify the field delimiter character in filename file | See DELIMITER Clause | Quoted String |
filename | Operating-system file to receive the rows. Default pathname is the current directory. | See UNLOAD TO File. | Quoted String |
variable | Host variable that contains the text of a valid SELECT statement | Must have been declared as a character data type | Language- specific |
Usage
Important: Use
the UNLOAD statement only with DB-Access.
The UNLOAD statement copies to a file the rows retrieved by a query. You must have the Select privilege on all columns specified in the SELECT statement. For information on database-level and table-level privileges, see GRANT statement.
You can specify a literal SELECT statement or a character variable that contains the text of a SELECT statement. (See SELECT statement.)
The following
example unloads rows whose value of
customer.customer_num
is
greater than or equal to 138
, and writes them to
a file named cust_file:UNLOAD TO 'cust_file' DELIMITER '!' SELECT * FROM customer WHERE customer_num> = 138;
The
resulting output file, cust_file, contains two
rows of data values:
138!Jeffery!Padgett!Wheel Thrills!3450 El Camino!Suite 10!Palo Alto!CA!94306!! 139!Linda!Lane!Palo Alto Bicycles!2344 University!!Palo Alto!CA!94301! (415)323-5400