How to I update property table reffered in mybatis - mybatis

Strange I couldn't find this easy answer in stackoverflow or mybatis guide. Thank you for those who is trying to help.
I have a class like this
Class One {
String name;
}
Class Two {
String name2;
One one;
}
I am using MyBatis #Update annotaion.
#Update("UPDATE One SET " +
"name=#{name}")
int updatefirst(Two two);
#Update("UPDATE Two SET " +
"name2=#{name}")
int updatesecondname(Two two);
How do I include the inner property that updates the foreign table one from the above query when I call updatesecondname?
Any help greatly appreciated.

Related

Spring JPA native query to '#IdClass' annotated table and getting "No Dialect mapping for JDBC type: 1111" [duplicate]

I'm working on a Spring JPA Application, using MySQL as database. I ensured that all spring-jpa libraries, hibernate and mysql-connector-java is loaded.
I'm running a mysql 5 instance. Here is a excerpt of my application.properties file:
spring.jpa.show-sql=false
spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.database-platform=org.hibernate.dialect.MySQL5Dialect
spring.datasource.url=jdbc:mysql://localhost/mydatabase
spring.datasource.username=myuser
spring.datasource.password=SUPERSECRET
spring.datasource.driverClassName=com.mysql.jdbc.Driver
When executing an integration test, spring startsup properly but fails on creating the hibernate SessionFactory, with the exception:
org.hibernate.MappingException: No Dialect mapping for JDBC type: 1111
I think my dialects should be Mysql5Dialect, I also tried the one explicitly stating InnoDB, and the two dialect options which don't indicate the version 5. But I always end up with the same 'No Dialect mapping for JDBC type: 1111' message.
My application.properties file resides in the test/resources source folder. It is recognized by the JUnit Test runner (I previously got an exception because of an typo in it).
Are the properties I'm setting wrong? I couldn't find some official documentation on these property names but found a hint in this stackoverflow answer: https://stackoverflow.com/a/25941616/1735497
Looking forward for your answers, thanks!
BTW The application is already using spring boot.
I got the same error because my query returned a UUID column. To fix that I returned the UUID column as varchar type through the query like "cast(columnName as varchar)", then it worked.
Example:
public interface StudRepository extends JpaRepository<Mark, UUID> {
#Modifying
#Query(value = "SELECT Cast(stuid as varchar) id, SUM(marks) as marks FROM studs where group by stuid", nativeQuery = true)
List<Student> findMarkGroupByStuid();
public static interface Student(){
private String getId();
private String getMarks();
}
}
Here the answer based on the comment from SubOptimal:
The error message actually says that one column type cannot be mapped to a database type by hibernate.
In my case it was the java.util.UUID type I use as primary key in some of my entities. Just apply the annotation #Type(type="uuid-char") (for postgres #Type(type="pg-uuid"))
There is also another common use-case throwing this exception. Calling function which returns void. For more info and solution go here.
I got the same error, the problem here is UUID stored in DB is not converting to object.
I tried applying these annotations #Type(type="uuid-char") (for postgres #Type(type="pg-uuid") but it didn't work for me.
This worked for me. Suppose you want id and name from a table with a native query in JPA. Create one entity class like 'User' with fields id and name and then try converting object[] to entity we want. Here this matched data is list of array of object we are getting from query.
#Query( value = "SELECT CAST(id as varchar) id, name from users ", nativeQuery = true)
public List<Object[]> search();
public class User{
private UUID id;
private String name;
}
List<User> userList=new ArrayList<>();
for(Object[] data:matchedData){
userList.add(new User(UUID.fromString(String.valueOf(data[0])),
String.valueOf(data[1])));
}
Suppose this is the entity we have
Please Check if some Column return many have unknow Type in Query .
eg : '1' as column_name can have type unknown
and 1 as column_name is Integer is correct One .
This thing worked for me.
Finding the column that triggered the issue
First, you didn't provide the entity mapping so that we could tell what column generated this problem. For instance, it could be a UUID or a JSON column.
Now, you are using a very old Hibernate Dialect. The MySQL5Dialect is meant for MySQL 5. Most likely you are using a newer MySQL version.
So, try to use the MySQL8Dialect instead:
spring.jpa.database-platform=org.hibernate.dialect.MySQL8Dialect
Adding non-standard types
In case you got the issue because you are using a JSON column type, try to provide a custom Hibernate Dialect that supports the non-standard Type:
public class MySQL8JsonDialect
extends MySQL8Dialect{
public MySQL8JsonDialect() {
super();
this.registerHibernateType(
Types.OTHER, JsonStringType.class.getName()
);
}
}
Ans use the custom Hibernate Dialect:
<property
name="hibernate.dialect"
value="com.vladmihalcea.book.hpjp.hibernate.type.json.MySQL8JsonDialect"
/>
If you get this exception when executing SQL native queries, then you need to pass the type via addScalar:
JsonNode properties = (JsonNode) entityManager
.createNativeQuery(
"SELECT properties " +
"FROM book " +
"WHERE isbn = :isbn")
.setParameter("isbn", "978-9730228236")
.unwrap(org.hibernate.query.NativeQuery.class)
.addScalar("properties", JsonStringType.INSTANCE)
.getSingleResult();
assertEquals(
"High-Performance Java Persistence",
properties.get("title").asText()
);
Sometimes when you call sql procedure/function it might be required to return something. You can try returning void: RETURN; or string (this one worked for me): RETURN 'OK'
If you have native SQL query then fix it by adding a cast to the query.
Example:
CAST('yourString' AS varchar(50)) as anyColumnName
In my case it worked for me.
In my case, the issue was Hibernate not knowing how to deal with an UUID column. If you are using Postgres, try adding this to your resources/application.properties:
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQL9Dialect
Another simple explanation might be that you're fetching a complex Type (Entity/POJO) but do not specify the Entity to map to:
String sql = "select yourentity.* from {h-schema}Yourentity yourentity";
return entityManager.createNativeQuery(sql).getResultList();
simply add the class to map to in the createNativeQuery method:
return entityManager.createNativeQuery(sql, Yourentity.class).getResultList();
In my case the problem was that, I forgot to add resultClasses attribute when I setup my stored procedure in my User class.
#NamedStoredProcedureQuery(name = "find_email",
procedureName = "find_email", resultClasses = User.class, //<--I forgot that.
parameters = {
#StoredProcedureParameter(mode = ParameterMode.IN, name = "param_email", type = String.class)
}),
This also happens when you are using Hibernate and returning a void function. AT least w/ postgres. It doesnt know how to handle the void. I ended up having to change my void to a return int.
If you are using Postgres, check that you don't have a column of type Abstime. Abstime is an internal Postgres datatype not recognized by JPA. In this case, converting to Text using TO_CHAR could help if permitted by your business requirements.
if using Postgres
public class CustomPostgreSqlDialect extends PostgreSQL94Dialect{
#Override
public SqlTypeDescriptor remapSqlTypeDescriptor(SqlTypeDescriptor sqlTypeDescriptor)
{
switch (sqlTypeDescriptor.getSqlType())
{
case Types.CLOB:
return VarcharTypeDescriptor.INSTANCE;
case Types.BLOB:
return VarcharTypeDescriptor.INSTANCE;
case 1111://1111 should be json of pgsql
return VarcharTypeDescriptor.INSTANCE;
}
return super.remapSqlTypeDescriptor(sqlTypeDescriptor);
}
public CustomPostgreSqlDialect() {
super();
registerHibernateType(1111, "string");
}}
and use
<prop key="hibernate.dialect">com.abc.CustomPostgreSqlDialect</prop>
For anybody getting this error with an old hibernate (3.x) version:
do not write the return type in capital letters. hibernate type implementation mapping uses lowercase return types and does not convert them:
CREATE OR REPLACE FUNCTION do_something(param varchar)
RETURNS integer AS
$BODY$
...
This is for Hibernate (5.x) version
Calling database function which return JSON string/object
For this use unwrap(org.hibernate.query.NativeQuery.class).addScalar() methods for the same.
Example as below (Spring & Hibernate):
#PersistenceContext
EntityManager em;
#Override
public String getJson(String strLayerName) {
String *nativeQuery* = "select fn_layer_attributes(:layername)";
return em.createNativeQuery(*nativeQuery*).setParameter("layername", strLayerName).**unwrap(org.hibernate.query.NativeQuery.class).addScalar**("fn_layer_attributes", **new JsonNodeBinaryType()**) .getSingleResult().toString();
}
Function or procedure returning void cause some issue with JPA/Hibernate, so changing it with return integer and calling return 1 at the end of procedure may solved the problem.
SQL Type 1111 represents String.
If you are calling EntityManager.createNativeQuery(), be sure to include the resulting java class in the second parameter:
return em.createNativeQuery(sql, MyRecord.class).getResultList()
After trying many proposed solutions, including:
https://stackoverflow.com/a/59754570/349169 which is one of the solutions proposed here
https://vladmihalcea.com/hibernate-no-dialect-mapping-for-jdbc-type/
it was finally this one that fixed everything with the least amount of changes:
https://gist.github.com/agrawald/adad25d28bf6c56a7e4618fe95ee5a39
The trick is to not have #TypeDef on your class, but instead have 2 different #TypeDef in 2 different package-info.java files. One inside your production code package for your production DB, and one inside your test package for your test H2 DB.

Play Framework 2.3 How to add unique constraint to sample application

Given the Play Framework 2.3 Computer Database sample application, I would like to practice adding a unique constraint on an attribute. Let's say I want the name attribute of the Computer class to be unique. I've tried to do this by adding a validate() function (and a getter) to Computer.java:
public List<ValidationError> validate() {
List<ValidationError> errors = new ArrayList<ValidationError>();
if(Computer.find.where().eq("name", getName()).findRowCount() != 0){
errors.add(new ValidationError("name", "Name must be unique. That value is already taken."));
}
return errors;
}
public String getName() {
return name;
}
This check works when creating new records in the database, however, this now causes a validation error when you update a Computer object but don't change the name. Is there a way to add a uniqueness constraint, similar to Rails? How can I validate uniqueness in Play?
Thanks!
UPDATE: see the answer by davide.
I ended up using the #Column(unique = true) constraint from the javax.persistence API. This doesn't generate an error in Play forms; instead, it throws a PersistenceException. Therefore I had to add change my controller to achieve the behavior I wanted. Both the create() and update() actions need a try/catch like this:
try {
computerForm.get().save();
} catch (PersistenceException pe) {
flash("error", "Please correct errors below.");
formData.reject("name", "Name conflict. Please choose a different name.");
return badRequest(createForm.render(computerForm));
}
UPDATE 2: each of the answers below is a possible solution
You need to exclude current entity from unique checking, i.e. like that:
if(Computer.find.where().eq("name", getName()).ne("id", getId()).findRowCount() != 0){
errors.add(new ValidationError("name", "Name must be unique."));
}
It will give you SQL query during update:
select count(*) from computer t0 where t0.name = 'Foo' and t0.id <> 123
And this during create:
select count(*) from computer t0 where t0.name = 'Foo' and t0.id is not null
P.S. ne() expression stands for Not Equal To and of course this approach assumes that your name field is Required
Edit: I sent you pull request with working solution, all you need is to add hidden field in your editForm like:
<input name="id" type="hidden" value='#computerForm("id").value'/>
Other thing is that you can simplify your model, i.e. don't need for getters for public fields.
I not sure if this answer your question, because I'm not familiar with Ruby syntax.
To "create a uniqueness constraint in the database" you can use the javax persistence API. Ebean will also recognize this.
To have a plain uniqueness constraint which involves a single field, you can use the #Column annotation:
#Entity
public class Computer extends Model {
...
#Column(unique = true)
public String name;
...
}
If you need some combination of fields to be unique, instead use the
#Table annotation
#Table(
uniqueConstraints=
#UniqueConstraint(columnNames={"name", "brand"})
)
#Entity
public class Computer extends Model {
...
public String name;
public String brand;
...
}
I hope it helps!

MyBatis: How to map "inverse" relationship?

My problem is to persist two classes that have a 1:n relationship:
public class DayRecord {
private Long id;
private List<TimeRecord> timeRecordsToday = new ArrayList<TimeRecord>(4);
...
}
public class TimeRecord {
private Long id;
...
}
So, in code, DayRecord knows TimeRecord.
create table DAY_RECORDS (
id int primary key,
);
create table TIME_RECORDS (
id int primary key,
day_record_id int not null,
foreign key (day_record_id) references DAY_RECORDS (id)
);
In database, TimeRecord knows DayRecord.
Can I save a DayRecord with all its TimeRecords in one step?
In Hibernate, I can set an inverse mapping and just save a DayRecord and all its TimeRecords will get saved, too. With MyBatis, I tried to save the classes independently from each other:
<mapper
namespace="de.stevenschwenke.java.javafx.xyz.DayRecordMapper">
<insert id="insertDayRecord"
parameterType="de.stevenschwenke.java.javafx.xyz.DayRecord">
insert into DAY_RECORDS (id) values (NEXT VALUE FOR DAY_RECORDS_SEQ);
</insert>
</mapper>
<mapper
namespace="de.stevenschwenke.java.javafx.xyz.TimeRecordMapper">
<insert id="insertTimeRecord"
parameterType="de.stevenschwenke.java.javafx.xyz.TimeRecord">
insert into TIME_RECORDS (id) values (NEXT VALUE FOR TIME_RECORDS_SEQ);
</insert>
</mapper>
But how can I save the DayRecord-ID inTimeRecord?
Ideas:
Give TimeRecord an attribute dayRecordId. This way, a cyclic dependency would be created. However, the mapping would take care of the dpenedency while saving.
In one transaction, save the DayRecord first, get its ID, set it in TimeRecords and save this object.
use a nested select-statement within insert like in the documentation
What is the best way to save both objects? Thanks for your help!
As jdevelop already mentioned, MyBatis is just a SQL wrapper. Because SQL doesn't offer a way to insert two objects that have a relationship, MyBatis can't do that either.
So here's my workaround: As I mentioned, I don't want to add a circular dependency by letting TimeRecord know about DayRecord. So I created a wrapper class just for inserting TimeRecords:
public class TimeRecordInsertWrapper {
public Long id;
public int hours;
public long dayRecordId;
[constructor/getter/setter omited but there with public access modifier]
}
First, I store the DayRecord and get it's ID. Then I create the wrapper object and store the TimeRecords:
public long insertDayRecord(DayRecord newRecord) {
SqlSession session = sqlSessionFactory.openSession();
try {
session.insert(
"de.stevenschwenke.java.javafx.xyz.DayRecordMapper.insertDayRecord",
newRecord);
for (TimeRecord tr : newRecord.getTimeRecordsToday()) {
TimeRecordInsertWrapper wrapper = new TimeRecordInsertWrapper(tr.getHours(), newRecord.getId());
session.insert("de.stevenschwenke.java.javafx.xyz.TimeRecordMapper.insertTimeRecord",
wrapper);
}
return newRecord.getId();
} finally {
session.commit();
session.close();
}
}
This way, I can use my nice one-way object model AND have the "right" mapping in the database.
Mybatis is just SQL mapping framework, it allows you to abstract SQL code from Java code and that's it, more or less. They are pretending to look like Hibernate with recent versions, but this leads to weird constructions in XML.
I would suggest to store the DayRecord and get it's it from selectKey, then use that ID in subsequent calls to the mapper. This is what actually happens inside the mapper, but complex XML implies complex FSM to built inside. So keep it simple and you're safe with myBatis, or use Hibernate.
What is even better, you can define custom DAO interfaces for the tasks, and then you can have some sort of Service layer with #Transactional attribute set. This requires mybatis-guice, but it works really great and you don't need to deal with transactions in your code (they are declarative).

Saving a Hashtable using Mongo & the Play framework?

I've got a model defined like the following...
#MongoEntity
public class Ent extends MongoModel{
public Hashtable<Integer, CustomType> fil;
public int ID;
public Ent(){
fil = new Hashtable<Integer, CustomType>();
}
}
CustomType is a datatype I've created which basically holds a list of items (among other things). At some point in my web application I update the hashtable from a controller and then read back the size of the item I just updated. Like the following...
public static void addToHash(CustomType type, int ID, int key){
//First I add an element to the list I'm storing in custom type.
Ent ent = Ent.find("byID",ID).first();
CustomType element = user.fil.get(key);
if(element == null) element = new CustomType();
element.add(type);
ent.save();
//Next I reset the variables and read back the value I just stored..
ent = null;
ent = User.find("byID",ID).first();
element = ent.fil.get(ID);
System.out.println("SIZE = " + element.size()); //null pointer here
}
As you can see by my above example I add the element, save the model and then attempt to read back what I have just added and it has not been saved. The above model Ent is a minimal version of the entire Model I'm actually using. All other values in the model including List's, String's, Integer's etc. update correctly when they're updated but this Hashtable I'm storing isn't. Why would this be happening and how could I correct it?
You should probably post on the play framework forum for better help..
Alternatives for a mongodb framework are morphia and springdata which have good documentation.
Not sure how Play maps a hash table to a document value, but it seems it cannot update just the hash table using a mongo operator.
You should be able to mark the whole document for update which would work but slower.

Accessing foreign key value (int) in Entity Framework

I just spent the last 3-4 hours trying to retrieve a foreign key value using linq to entities and a stored procedure. Any advice is much appreciated.
public JsonResult GetEvents(double? start, double? end)
{
AnoEntities _dbAno = new AnoEntities();
var events = _dbAno.Events_GetByDateRange(fromDate, toDate);
var eventList = from e in events
select new
{
id = e.id,
title = e.title,
className = e.event_types.type.ToString()
};
return Json(eventList.ToArray());
}
type_id is the foreign key value that i'm trying to reach. I can't get it so appear in the entity data model and I can't seem to get to it. e.event_types and e.event_typesReference are both null so things like e.event_typesReference.EntityKey.EntityKeyValues.First().Value.ToString() aren't working.
Thanks!
I don't see any .Include methods or Load methods on even_types and I'm assuming your returning IEnumerable from your _dbAno.Events_GetByDateRange(fromDate, toDate). Like Craig pointed out in the comments if your return type of GetByDateRange is IQueryable you'd be projecting and EF should eager load for you.
Just a reminder that implicit lazy loading isn't supported out of the box in Entity Framework 1.0. You'll need to manually load the event_types with Load() or use the Include method on ObjectQuery.