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Learning iBATIS - The SqlMap API

The SqlMapClient interface has over 30 methods on it.

#1 The queryForObject() methods

The queryForObject() methods are used to get a single row from the database
into a Java object, and come with two signatures:
■ Object queryForObject(String id, Object parameter) throws SQLException;
■ Object queryForObject(String id, Object parameter, Object result)
throws SQLException;


The second form is useful if you have an object that cannot be easily
created because of a protected constructor or the lack of a default constructor.


#2 The queryForList() methods
The queryForList() methods are used to get one or more rows from the database
into a List of Java objects, and like queryForObject(), they also come in two versions:
■ List queryForList(String id, Object parameter) throws SQLException;
■ List queryForList(String id, Object parameter, int skip, int max)
throws SQLException;

#3 The queryForMap() methods
The queryForMap() methods return a Map (instead of a List) of one or more rows
from the database as Java objects. Just like the other query methods, it has two
forms as well:

■ Map queryForMap(String id, Object parameter, String key) throws SQLException;
■ Map queryForMap(String id, Object parameter, String key, String value)
throws SQLException;

By using the first method, you could create a Map that had the key
property as the key to the map and the full  bean as the value. Using
the second method, you could create a Map that had the key property as
the key to the map, and only the value as the value.

#4 The insert method
As you may have guessed, the insert method is used to execute mapped statements that correspond to the SQL insert statement:

Object insert(String id, Object parameterObject) throws SQLException;
e.g.

<insert id="insertWithInlineInfo">
insert into account (
accountId,
username, password,
memberSince,
firstName, lastName,
address1, address2,
city, state, postalCode,
country, version
) values (


#accountId:NUMBER#,
#username:VARCHAR#, #password:VARCHAR#,
#memberSince:TIMESTAMP#,
#firstName:VARCHAR#, #lastName:VARCHAR#,
#address1:VARCHAR#, #address2:VARCHAR#,
#city:VARCHAR#, #state:VARCHAR#, #postalCode:VARCHAR#,
#country:VARCHAR#, #version:NUMBER#
)
</insert>

Codes;

Account account = new Account();
account.setAccountId(new Integer(9999));
account.setUsername("inlineins");
account.setPassword("poohbear");
account.setFirstName("Inline");
account.setLastName("Example");
sqlMapClient.insert("Account.insertWithInlineInfo", account);




#5 The update method
The update method is used to execute mapped statements that correspond to SQL update statement:

int update(String id, Object parameterObject) throws SQLException;

#6 The delete method
The delete method is almost identical to the update method, but instead of being used to execute update SQL statements, it is used to execute delete statement:

int delete(String id, Object parameterObject) throws SQLException;








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