Reference Information

Valid SQL-JDBC Datatype Mappings

Table 3-1 and Table 3-2 in Chapter 3 describe the default mappings between Java classes and SQL datatypes that are supported by the Oracle JDBC drivers. Compare the contents of the Standard JDBC Datatypes, Java Native Datatypes and Oracle SQL Datatypes columns in Table 3-1 and Table 3-2 with the contents of Table 8-1 below.

Table 8-1 lists all of the possible Java classes to which a given SQL datatype can be validly mapped. The Oracle JDBC drivers will support these "non-default" mappings. For example, to materialize SQL CHAR data as an oracle.sql.CHAR, use getCHAR(). To materialize it as a java.math.BigDecimal, use getBigDecimal().

Table 8-1 Valid SQL Datatype-Java Class Mappings

This SQL datatype:	Can be materialized as these Java classes:
CHAR, NCHAR,VARCHAR2,	oracle.sql.CHAR
NVARCHAR2, LONG	java.lang.String
	java.sql.Date
	java.sql.Time
	java.sql.Timestamp
	java.lang.Byte
	java.lang.Short
	java.lang.Integer
	java.lang.Long
	java.lang.Float
	java.lang.Double
	java.math.BigDecimal
	byte, short, int, long, float, double
DATE	oracle.sql.DATE
	java.sql.Date
	java.sql.Time
	java.sql.Timestamp
	java.lang.String
NUMBER	oracle.sql.NUMBER
	java.lang.Byte
	java.lang.Short
	java.lang.Integer
	java.lang.Long
	java.lang.Float
	java.lang.Double
	java.math.BigDecimal
	byte, short, int, long, float, double
RAW, LONG RAW	oracle.sql.RAW
	byte[]
ROWID	oracle.sql.CHAR
	oracle.sql.ROWID
	java.lang.String
BFILE	oracle.sql.BFILE
BLOB	oracle.sql.BLOB
	oracle.jdbc2.Blob
CLOB, NCLOB	oracle.sql.CLOB
	oracle.jdbc2.Clob
OBJECT	oracle.sql.STRUCT
	oracle.SqljData
	oracle.jdbc2.Struct
REF	oracle.sql.REF
	oracle.jdbc2.Ref
TABLE (nested), VARRAY	oracle.sql.ARRAY
	oracle.jdbc2.Array
any of the above SQL types	oracle.sql.CustomDatum or oracle.sql.Datum

Notes:

The type UROWID is not supported.

oracle.sql.Datum is an abstract class. The value passed to a parameter of type oracle.sql.Datum must be of the Java type corresponding to the SQL type. Likewise, the value returned by a method with return type oracle.sql.Datum must be of the Java type corresponding to the SQL type.

The mappings to oracle.sql classes are optimal if no conversion from SQL format to Java format is necessary.