|
Use the appropriate getXXX and setXXX methods for the type
For performance reasons, use the recommended getXXX method
when retrieving values, and use the recommended setXXX method when
setting values for parameters.
JDBC is permissive. It lets you use java.sql.ResultSet.getFloat to
retrieve an int, java.sql.ResultSet.getObject to retrieve any type,
and so on. (java.sql.ResultSet and java.sql.CallableStatement provide getXXX methods,
and java .sql.PreparedStatement and java.sql.CallableStatement provide setXXX methods.)
This permissiveness is convenient but expensive in terms of performance.
The following table shows the recommended getXXX methods for given java.sql (JDBC)
types, and their corresponding SQL types.
Table 1. Mapping of java.sql.Types to SQL types
| Recommended getXXX Method |
java.sql.Types |
SQL types |
| getLong |
BIGINT |
BIGINT |
| getBytes |
BINARY |
CHAR FOR BIT DATA |
| getBlob |
BLOB |
BLOB |
| getString |
CHAR |
CHAR |
| getClob |
CLOB |
CLOB |
| getDate |
DATE |
DATE |
| getBigDecimal |
DECIMAL |
DECIMAL |
| getDouble |
DOUBLE |
DOUBLE PRECISION |
| getDouble |
FLOAT |
DOUBLE PRECISION |
| getInt |
INTEGER |
INTEGER |
| getBinaryStream |
LONGVARBINARY |
LONG VARCHAR FOR BIT DATA |
| getAsciiStream, getUnicodeStream |
LONGVARCHAR |
LONG VARCHAR |
| getBigDecimal |
NUMERIC |
DECIMAL |
| getFloat |
REAL |
REAL |
| getShort |
SMALLINT |
SMALLINT |
| getTime |
TIME |
TIME |
| getTimestamp |
TIMESTAMP |
TIMESTAMP |
| getBytes |
VARBINARY |
VARCHAR FOR BIT DATA |
| getString |
VARCHAR |
VARCHAR |
| None supported. You must use XMLSERIALIZE and then the
corresponding getXXX method. |
SQLXML |
XML |
|
