Apache Derby—Off to the Races: Includes Details of IBM® Cloudscape™

Retrieving Column Values

Many of the examples up to this point use the getString() method to turn a column value into a Java data type. As one might expect, getString() returns the contents of the column in the result set as a character string. There are a number of these methods, but before discussing the purpose of getX() methods, some understanding of SQL and Java data types is required.

Most SQL data types have a corresponding Java data type, and the following table lists all of the types available in Apache Derby, as well as the corresponding getX() methods associated with their retrieval.

Table 9-4. SQL versus Java Data Types

SQL Data Type	Java.sql.Types	getX() Method
SMALLINT	SMALLINT	getShort()
INTEGER	INTEGER	getInt()
BIGINT	BIGINT	getLong()
DECIMAL ...