Get the id of last inserted record in mybatis - java

I am newbie to mybatis. I am trying to get the id of last inserted record. My database is mysql and my mapper xml is
<insert id="insertSelective" parameterType="com.mycom.myproject.db.mybatis.model.FileAttachment" >
<selectKey resultType="java.lang.Long" keyProperty="id" order="AFTER" >
SELECT LAST_INSERT_ID() as id
</selectKey>
insert into fileAttachment
<trim prefix="(" suffix=")" suffixOverrides="," >
<if test="name != null" >
name,
</if>
<if test="attachmentFileSize != null" >
size,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides="," >
<if test="name != null" >
#{name,jdbcType=VARCHAR},
</if>
<if test="attachmentFileSize != null" >
#{attachmentFileSize,jdbcType=INTEGER},
</if>
</trim>
</insert>
I thought statement written here 'SELECT LAST_INSERT_ID() as id' should return id of last inserted record but I am getting always 1 after inserting the record.
My mapper.java class I have method
int insertSelective(FileAttachment record);
In my dao class I am using
int id = fileAttachmentMapper.insertSelective(fileAttachment);
I am getting value of Id always 1 when new record is inserted. my Id field is auto incremented and records are inserting properly.

The id is injected in the object:
int num_of_record_inserted = fileAttachmentMapper.insertSelective(fileAttachment);
int id = fileAttachment.getId();
What selectKey does is to set the id in the object you are inserting, in this case in fileAttachment in its property id and AFTER record is inserted.

You only need to use
<insert id="insert" parameterType="com.mycom.myproject.db.mybatis.model.FileAttachment" useGeneratedKeys="true" keyProperty="id" keyColumn="id">
There is no need of executing select query inside insert tag in MyBatis. It provides you new parameter for insert operation.Here define useGeneratedKeys="true", keyProperty="id", keyColumn="id".You can retrive value for id in following way
FileAttachment fileAttachment=fileAttachmentMapper.insertSelective(fileAttachment);
Integer id=fileAttachment.getId();
fileAttachment.getId() is used because in insert tag keyColumn="id" is define and you will get all return values inside fileAttachment reference of FileAttachment.

In fact, MyBatis has already provided this feature.You can use the option : "useGeneratedKeys" to get the last insert id.
Here is the explanation from MyBatis.(If you want to know more detailed info, you can go to MyBatis official page).
useGeneratedKeys (insert and update only) This tells MyBatis to use the JDBC getGeneratedKeys method to retrieve keys generated internally by the database (e.g. auto increment fields in RDBMS like MySQL or SQL Server). Default: false
If you are using xml:
<insert id="" parameterType="" useGeneratedKeys="true">
If you are using annotation:
#Insert("your sql goes here")
#Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")
int insert(FileAttachment fileAttachment) throws Exception;
Once you finish insert operation, the fileAttachment's setId() method will be invoked, and is set to id of last inserted record. You can use fileAttachment's getId() to get the last insert id.
I do hope this will help you.

I think the 1 that is being returned refers to the number of records that is updated/inserted. I think the id is set on the fileAttachment parameter that you passed to the call to insertSelective.

I hope in the writer, you can have a custom composite writer and there you can get the inserted ids.

(1) Adding on to Ruju's answer, in the insert statement you need to define attribute useGeneratedKeys=true, parameterType="object", keyProperty="objectId" and keyColumn="objectId" should be set with same primary key column name (objectId) from the table that stores the object record. The primary key column (objectId) should be set to AUTO_INCREMENT in the database table.
(2) When the insert statement is triggered the new generated primary key (objectId) will be stored in object, and u can retrieve it by accessing objectId property through using this methods (object.getObjectId() or object.objectId). Now this should give the exact and new generated primary. It worked for me....

Configuration need with codeGenerator :
<table schema="catalogue" tableName="my_table" >
<generatedKey column="my_table_id" sqlStatement="JDBC" identity="true" />
<columnOverride column="my_table_id" isGeneratedAlways="true"/>
</table>
http://www.mybatis.org/generator/configreference/generatedKey.html
after code generation the insert include auto update for the id field

After struggling alot, I got the following solution:
Use Case: if you are using sequence for generating primary key. and you want the id inserted to db
in xml:
<insert id="createEmployee"
parameterType="com.test.EmployeeModel">
<selectKey keyProperty="employeeId" keyColumn="EMPLOYEE_ID"
resultType="Long" order="BEFORE">
select EMPLOYEE_SEQ.NEXTVAL FROM DUAL
</selectKey>
INSERT INTO EMPLOYEE(EMPLOYEE_ID,EMPLOYEE_NAME)
VALUES
(#{employeeId,jdbcType=NUMERIC},#{EMPLOYEE_NAME,jdbcType=VARCHAR})
</insert>
in java side:
interface
public void createEmployee(EmployeeModel request);
in dao
getMapper().createEmployee(model);
getClient().commit();
Long employeeId= model.getEmployeeId();
System.out.println("Recent Employee Id: "+employeeId)

Related

Mybatis selectKey not returning sequence value

I'm using the below insert query in mybatis. In ibatis, the same query returned seq_consumer_id.nextval to the calling method in java, and inserted the same into the consumer_id column. But in mybatis, return value of the method is always 1 (I'm assuming its the no of rows inserted), though consumer_id column is correctly updated from sequence. Can't we generate the key, insert it and return the same to java class in mybatis ?
<insert id="insertConsumer" parameterType="com.enrollment.vo.ConsumerVO">
<selectKey keyProperty="id" resultType="int" order="BEFORE">
select seq_consumer_id.nextval as id from dual
</selectKey>
insert into quotation_consumer (consumer_id, consumer_type, dob,
create_date, ENROLLMENT_INDICATOR, QUOTE_ID,IS_PRIMARY)
values(#{id},#{type.id}, #{birthdate, jdbcType=DATE}, default, #{enrollmentIndicator},
#{quoteId},#{isPrimary})
</insert>
Indeed the method returns the number of affected rows.
Sequence id is stored in ìd property of com.enrollment.vo.ConsumerVO passed as parameter.

How to autogenerate two values when inserting at runtime?

I'm using MyBatis as DB framework in JAVA and I'm trying to generate automatically two values when inserting rows in a table: the task id and another value. This is my query:
<insert id="insertTwoValuesSequentialluy" parameterType="com.example.autogenerated.Task" >
<selectKey resultType="java.lang.String" keyProperty="taskId" order="BEFORE" >
select MY_TASK_ID_SEQUENCE.nextval from dual
</selectKey>
insert into DYDA_D.TASK_TABLE (taskId, otherVariable, autogeneratedValue)
values ( #{taskId,jdbcType=VARCHAR},
#{otherVariable,jdbcType=VARCHAR},
MY_SECOND_SEQUENCE.nextval = #{autogeneratedValue,jdbcType=VARCHAR})
</insert>
The code works fine but I'm having the following problem: while at runtime the Task instance gets its member taskId setted, it doesn't happen the same with autogeneratedValue, although when I check the database I can see the column matching autogeneratedValue isn't null for this new row. How can I get autogeneratedValue setted at runtime with no need of making a select query?
PS: don't pay attention to commas and the like, I have lots of columns and I've deleted most of them and changed names on the rest for this snippet. My point with the code is for you to see how I've generated the values, tags I've used etc.
You can do this like this:
<insert id="insertTwoValuesSequentialluy"
parameterType="com.example.autogenerated.Task"
useGeneratedKeys="true"
keyProperty="taskId,autogeneratedValue"
keyColumn="taksId,autogeneratedValue">
insert into DYDA_D.TASK_TABLE (taskId, otherVariable, autogeneratedValue)
values (MY_TASK_ID_SEQUENCE.nextval,
#{otherVariable,jdbcType=VARCHAR},
MY_SECOND_SEQUENCE.nextval)
</insert>

will <selectKey> generate new id for each insert in MyBatis?

<insert id="insertIntoScheduleReportUserLink" parameterType="com.mypackage.model.ScheduleReport">
<selectKey keyProperty="id" resultType="java.lang.Integer" order="BEFORE">
select NEXTVAL('schedule_report_user_link_sequence')
</selectKey>
INSERT INTO schedule_report_user_link(
id, schedule_report_detail_id, to_user_id)
<foreach collection="selectedUsers" item="user" separator=",">
VALUES (#{id}, #{scheduleReportDetail.id}, #{user.id})
</foreach>;
</insert>
Here I am using for each loop to multiple insert. I need to know if selectKey generate new id for each insert?
Is there any better approach?
The loop is running only of the insert section not on the key generation part.
So its seems the key will be generated once.
Don't depend on hypothesis run for a little data and see it for your self.

How can I get an id for a new record in a generic way? (JOOQ 3.4 with Postgres)

With jooq 3.4 I can't figure out how to do this (with Postgresql):
Query query = dsl.insertInto(TABLE)
.set(TABLE.ID, Sequences.TABLE_ID_SEQ.nextval());
but in a case when I don't know which is the exact table, something like this:
TableImpl<?> tableImpl;
Query query = dsl.insertInto(tableImpl)
.set(tableImpl.getIdentity(), tableImpl.getIdentity().getSequence().nextval());
Is it somehow possible?
I tried this:
dsl.insertInto(tableImpl)
.set(DSL.field("id"),
tableImpl.getSchema().getSequence("table_id_seq").nextval())
This works but I still don't know how to get the sequence name from the TableImpl object.
Is there a solution for this? Or is there a problem with my approach?
In plain SQL I would do this:
insert into table_A (id) VALUES nextval('table_A_id_seq');
insert into table_B (table_A_id, some_val) VALUES (currval('table_A_id_seq'), some_val);
So I need the value or a reference to that id for later use of the id that was generated for the inserted record as default, but I don't want to set any other values.
jOOQ currently doesn't have any means of associating a table with its implicitly used sequence for the identity column. The reason for this is that the sequence is generated when the table is created, but it isn't formally connected to that table.
Usually, you don't have to explicitly set the serial value of a column in a PostgreSQL database. It is generated automatically on insert. In terms of DDL, this means:
CREATE TABLE tablename (
colname SERIAL
);
is equivalent to specifying:
CREATE SEQUENCE tablename_colname_seq;
CREATE TABLE tablename (
colname integer NOT NULL DEFAULT nextval('tablename_colname_seq')
);
ALTER SEQUENCE tablename_colname_seq OWNED BY tablename.colname;
The above is taken from:
http://www.postgresql.org/docs/9.3/static/datatype-numeric.html#DATATYPE-SERIAL
In other words, just leave out the ID values from the INSERT statements.
"Empty" INSERT statements
Note that if you want to create an "empty" INSERT statement, i.e. a statement where you pass no values at all, generating a new column with a generated ID, you can use the DEFAULT VALUES clause.
With SQL
INSERT INTO tablename DEFAULT VALUES
With jOOQ
DSL.using(configuration)
.insertInto(TABLENAME)
.defaultValues()
.execute();
Returning IDs
Note that PostgreSQL has native support for an INSERT .. RETURNING clause, which is also supported by jOOQ:
With SQL
INSERT INTO tablename (...) VALUES (...) RETURNING ID
With jOOQ
DSL.using(configuration)
.insertInto(TABLENAME, ...)
.values(...)
.returning(TABLENAME.ID)
.fetchOne();

Insert only if row doesn't exist

I am using PreparedStatement to prepare sql queries. I want to insert a row in table if and only if it doesn't exist.
I tried this -
INSERT INTO users (userId) VALUES (?) ON DUPLICATE KEY UPDATE userId = ?
But this will unnecessarily update the userId.
How can i insert the userId here ?
INSERT INTO users
(userId)
SELECT ?
WHERE NOT EXISTS
(
SELECT *
FROM users
where userId = ?
)
You may use
INSERT IGNORE INTO users (userId) VALUES (?)
But you should understand why do you want ignore errors.
on duplicate key does not work correctly when the table is an innodb. It creates exactly the problem you are describing. If you need the functionality of an innodb, then should you first check the existence of the row, otherwise can you convert the table to a myisam table.
edit: if you need to check the existence of the row before the decision to insert or update, then would I advice you to use a stored procedure.
DELIMITER //
CREATE PROCEDURE adjustusers(IN pId int)
BEGIN
DECLARE userid int;
select count(id) into userid from users where id = pId;
if userid = 1 then
update users set id = pId where id = pId;
else
insert into users(id) values(pId);
end if;
END //
DELIMITER ;
A stored procedure is precompiled, just as a prepared statement. Hence no SQL injection problems and some more functionality and only one call to the database.

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