SQL is a standard and it is implemented by almost all database server vendors. As part of this standard, the grammar of the SQL is defined and it consists of the information about various data types that can be supported by a database server. But not every datatype that is part of SQL standard is suppored by the popular servers like ORACLE.

A JDBC API is designed to deal with different kinds of database servers. Javasoft has provided a class with the name java.sql.Types with a set of constants represeting various data types that are part of SQL standard. We call these data types as JDBC data types.

Below constants have been defined as part of java.sql.Types calls... You can get more info on this class through API @ http://docs.oracle.com/javase/6/docs/api/java/sql/Types.html

public static final int BIT;
public static final int TINYINT;
public static final int SMALLINT;
public static final int INTEGER;
public static final int BIGINT;
public static final int FLOAT;
public static final int REAL;
public static final int DOUBLE;
public static final int NUMERIC;
public static final int DECIMAL;
public static final int CHAR;
public static final int VARCHAR;
public static final int LONGVARCHAR;
public static final int DATE;
public static final int TIME;
public static final int TIMESTAMP;
public static final int BINARY;
public static final int VARBINARY;
public static final int LONGVARBINARY;
public static final int NULL;
public static final int OTHER;
public static final int JAVA_OBJECT;
public static final int DISTINCT;
public static final int STRUCT;
public static final int ARRAY;
public static final int BLOB;
public static final int CLOB;
public static final int REF;
public static final int DATALINK;
public static final int BOOLEAN;
public static final int ROWID;
public static final int NCHAR;
public static final int NVARCHAR;
public static final int LONGNVARCHAR;
public static final int NCLOB;
public static final int SQLXML;