We Keep Coding

java Dynamic where clause based on user search

Hi i need to dynamically build a query based on user selection. I cant write where conditions with if statement because i have 50 columns in table.is there a way without if statements?

You can look on CrtitriaAPI or you can use hibernate feature
Query by example
Actually if you are using spring with spring data module you can look into Specifications
Please look into below links:
https://dzone.com/articles/hibernate-query-example-qbe
https://vladmihalcea.com/query-entity-type-jpa-criteria-api/
https://spring.io/blog/2011/04/26/advanced-spring-data-jpa-specifications-and-querydsl/

Do you mean how to avoid the sql injection like concatenating sql statements at runtime?
static final String INVOICE_QUERY = "SELECT inv from Invoice inv WHERE (:createDate IS NULL OR inv.createDate = :createDate) AND (:quantity IS NULL OR inv.quantity = :quantity) AND (:custName IS NULL OR inv.custName = :custName)";
Session session = getHibernateTemplate().getSessionFactory().openSession();
Query query = session.createQuery(INVOICE_QUERY);
query.setDate("createDate", createDate);
if(quantity != null)
query.setLong("quantity", quantity);
else
query.setBigInteger("quantity", null);
if(StringUtils.isNotBlank(custName))
query.setString("custName", custName);
else
query.setString("custName", null);
return query.list();

How to use net.java.ao.Query to query issues?

I have this select in PostgreSQL:
SELECT "field_1", "field_2","field_3", MIN(COALESCE(NULLIF("field_4",'') ,'TBD')) MINDP,MIN("field_5") MINBOD FROM "MY_TABLE" GROUP BY "field_1", "field_2","field_3"
And I want to use net.java.ao.Query to query my database. My function:
import net.java.ao.Query;
public List<myClass> find() {
String SQL = "SELECT \"field_1\", \"field_2\",\"field_3\", MIN(COALESCE(NULLIF(\"field_4\",'') ,'TBD')) MINDP,MIN(\"field_5\") MINBOD FROM \"MY_TABLE\" GROUP BY \"field_1\", \"field_2\",\"field_3\""
return newArrayList(ao.find(myClass.class, Query.select(SQL)));
}
The problem is: this code return all issues of my table.
When I run this SQL in postgreSQL console it works fine.
My code has different results than SQL console.
Does anybody know why is this happening?

Old question but if somebody steps over this -
Query.select() is not meant to put plain SQL into. It is more of a builder to create 'database independant' query. See some examples here: Finding entities
public MyEntity[] findMyEntities(String fieldValue) {
final Query query = Query.select()
.where("FIELD_VALUE = ?", fieldValue);
// evaluates to something like this
// SELECT * FROM MY_ENTITY WHERE FIELD_VALUE = x;
return ao.find(MyEntity.class, query);
}
This is why there's another method (which you used in your comment), that can handle plain SQL (findWithSQL).
Attention Query and find() often do not work as expected, so you might not get your original query to work using the query builder.

ORMLite or Query across multiple tables

I am trying to query a table based on criteria from a join table using ORMLite.
Here is how I would express the query I am trying to write in tsql:
select * from media m inner join file f on m.fileId = f.fileId
where m.isNew = 1 OR f.isNew = 1
The result should be a list of media records where either the media record or the corresponding file record has isNew = 1.
I have read through the documentation on using OR in ORMLite, but all of the examples use a single table, not joining. Likewise I have read the documentation on joins, but none of the examples include a where clause that spans both tables. Is there any way besides a raw query to do this?
I had a look at this question: https://stackoverflow.com/a/12629645/874782 and it seems to ask the same thing, but the accepted answer produces an AND query, not an OR. Here is my code that I used to test that theory:
public List<Media> getNewMedia() {
Session session = getSession();
Account account = session.getSelectedAccount();
ContentGroup contentGroup = account.getSelectedContentGroup();
List<Media> results = null;
try {
QueryBuilder<Category, Integer> categoryQueryBuilder = getHelper().getCategoryDao().queryBuilder();
categoryQueryBuilder.where().eq("group_id", contentGroup.getId());
QueryBuilder<MediaCategory, Integer> mediaCatQb = getHelper().getMediaCategoryDao().queryBuilder();
mediaCatQb = mediaCatQb.join(categoryQueryBuilder);
QueryBuilder<FileRecord, Integer> fileQueryBuilder = getHelper().getFileDao().queryBuilder();
fileQueryBuilder.where().ge("lastUpdated", contentGroup.getLastDownload());
QueryBuilder<Media, Integer> mediaQb = getHelper().getMediaDao().queryBuilder();
mediaQb.where().eq("seen", false);
// join with the media query
results = mediaQb.join(fileQueryBuilder).join(mediaCatQb).query();
} catch (SQLException e) {
Log.e(TAG, "Sql Exception", e);
}
return results;
}
For the sake of completion, this is querying for a slightly more complex example than the one I gave above, this one expressed in tsql would be
select * from Media m join FileRecord f on m.fileRecordId = f.fileRecordId
where m.seen = false OR f.lastUpdated >= lastUpdateDate
When I run it, it is actually doing an AND query, which is what I would expect based on two joins with independent where clauses.
I think the key issue is that a where clause is inherently tied to a table, because it is performed on a QueryBuilder object which comes from a Dao that is specific to that table. How can I get around this?

I think what you are looking for is joinOr search for it in the ORMLite docs.
Like join(QueryBuilder) but this combines the WHERE statements of two
query builders with a SQL "OR".

Mapping RawSql Result to Object in Java Ebean

Let's say I have a class Article which is automatically mapped by Java Ebean as a database table.
For this table I wanted to retrieve entries via a RawSql query, because I find SQL more simple when it gets to complex queries with many joins and such. By far I have managed to give my SQL statement to the Parser. The query is correct, I already checked that.
The only problem is, that I don't know, how to map the database results to my Article class. I know, that there is a columnMapping(...) method but honestly, I am to lazy to map every single column manually...
Isn't there another way to just like myResults.mapToClass(Article.class) to retrieve something like a List<Article>?
This is the code I already have:
Finder<String, Article> find = new Finder<String, Article>(
String.class, Article.class);
String sql = "SELECT * FROM article [...]";
RawSql rawSql = RawSqlBuilder.parse(sql).create();
List<Article> returnList = find.setRawSql(rawSql).findList();
Alternatively:
Finder<String, Article> find = new Finder<String, Article>(
String.class, Article.class);
String sql = "SELECT id, title, sub_title FROM article [...]";
RawSql rawSql = RawSqlBuilder.parse(sql)
.columnMapping("id", "id")
.columnMapping("title", "title")
.columnMapping("sub_title", "subTitle")
.create();
List<Article> resultList = find.setRawSql(rawSql).findList();

A lot of happened in Ebean since the question was asked, but I think the problem is still valid. the new RawSqlBuilder.tableMapping() makes things easier as can be seen in the code below, but afaik it still needs manual mapping of all attributes (no SELECT table.* FROM table)
I have this exact problem, and worked around this by creating a helper object (#Entity/#Sql) that I map to. E.g. CustomerWithPurchaseStats.
Extract:
#Entity
#Sql
public class CustomerWithPurchaseStats {
#OneToOne
private Customer customer;
...
And in the DAO:
public List<CustomerWithPurchaseStats> getAllCustomersWithPurchaseStats() {
StringBuilder sql = new StringBuilder("SELECT cu.id, <manually add all fields you need mapped ").append(" FROM customer cu ");
RawSqlBuilder rawSqlBuilder = RawSqlBuilder.parse(sql.toString());
rawSqlBuilder.tableAliasMapping("cu", "customer").create();
return Ebean.find(CustomerWithPurchaseStats.class)
.setRawSql(rawSqlBuilder.create())
.findList();
}

hibernate java select queries

i am new to this and today i tried to play hibernate with a method that returns the result of selected row...if is selected then it can return the result in int.. here is my method
public int validateSub(String slave, String source, String table){
Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
Query q = session.createQuery("from Subscribers where slave = :slave AND source = :source AND tbl = :tbl");
q.setParameter("slave", slave);
q.setParameter("source", source);
q.setParameter("tbl", table);
int result = q.executeUpdate();
return result;
}
from this method i tried to validate the 3 values that i get from the Subscribers table but at the end i tried to compile having this error
Exception in thread "Thread-0" org.hibernate.hql.QueryExecutionRequestException: Not supported for select queries [from com.datadistributor.main.Subscribers where slave = :slave AND source = :source AND tbl = :tbl]

You can have a look at the below links that how executeUpdate works, one is from the hibernate docs and other the java docs for JPA which defines when the exception is thrown by the method
http://docs.oracle.com/javaee/6/api/javax/persistence/Query.html#executeUpdate()
https://docs.jboss.org/hibernate/orm/3.2/api/org/hibernate/Query.html#executeUpdate()
Alternatively you can use
List list = query.list();
int count = list != null ? list.size() : 0;
return count;

you are running a select query, Eventhough you are not using the select keyword here hibernate will add that as part of the generated SQL.
what you need to do to avoid the exception is the say
q.list();
now, this will return a List (here is the documentation).
if you are trying to get the size of the elements you can say
Query q = session.createQuery("select count(s) from Subscribers s where slave = :slave AND source = :source AND tbl = :tbl");
Long countOfRecords = (Long)q.list().get(0);
you can execute update statements as well in HQL, it follows a similar structure as SQL (except with object and properties).
Hope this helps.

here you want to select record so it is posible without select key word
sessionFactory sesionfatory;
ArrayList list = (ArrayList)sessionfactory.getCurruntSession().find(from table where name LIKE "xyz");
long size = list.get(0);

I also happened to make the same mistake today.
Your SQL statement is not correct.
You can try:
DELETE from Subscribers WHERE slave = :slave AND source

Try this:
int result = q.list().size();