How to create a dynamic query using EOD SQL? - sql

This should be fairly simple, though I can't seem to find a single example.
I want to create a query looking like this:
SELECT column_name FROM table_name WHERE column_name IN (value1,value2,...)
As an option I could append OR-clauses to the end of the query.
The code I have written so far keeps blowing up with a Nullpointer:
#Select(sql = "select storename from broadcastrecipient where storecity in (?{1})")
public List<String> getStoresForCities(List<String> theCities) throws SQLException;
Thanks in advance.
//Abean
NOTE: I forgot to add some info about my env: PostGres 8.3, Java 1.6 and EOD SQL 0.9.
Thank you Jason.
For those who like to know, the query looks something like this:
#Select(sql = "select distinct(storename) from broadcastrecipient where storecity = any (?{1})", disconnected=true)
public List<String> getStoresForCities(String[] theCities) throws SQLException;
And I also needed to implement a TypeMapper class to map SQL-array to Java array.

I would suggest looking at EoD SQL 2.0: https://eodsql.dev.java.net/
Then take a look at the QueryTool.select() method which is designed exactly for this situation.
EoD SQL 0.9 has no functionality to cope with this sort of query built in.
A really ugly hack is to create a temp table, and populate it with your array data. Then run the query as:
#Select("SELECT storename FROM broadcastrecipient WHERE storecity IN (SELECT * FROM tmp_cities)")
public List<String> getStoresForCurrentCities();

Related

How to create query with Spring Data JPA?

Please help me. I can not create query from native sql using spring data.
How do I convert the following expression?
select distinct brand, model from cars
where brand like '%:query%' or model like '%:query%' limit 2;
You could use projections with Spring Data JPA, something of the likes of:
interface SimpleCar {
String getBrand();
String getModel();
}
and then:
List<SimpleCar> findDistinctByBrandLikeOrModelLike(String query);
You can review here for different options to query a DB with some examples.
By the way, if you want to see what queries your methods are executing you can activate DEBUG logging mode in log4j for org.springframework package or org.hibernate (if you're using Hibernate)
that helped me, hopefully you too
https://www.petrikainulainen.net/programming/spring-framework/spring-data-jpa-tutorial-three-custom-queries-with-query-methods/
Use:
#Query("select distinct brand, model from cars " +
"where brand like %:query% or model like %:query% limit 2")
public List<Car> find(#Param("query") String query);
Basically what you had but without the speech marks.

JPA native query gives incorrect output

I know this may sound silly but I've been stuck on this problem for too long!
I'm querying a PostgreSQL repository through JPA using native SQL queries. One of my queries looks like this:
#Query(value = "select * from gs where ?1 = ?2", nativeQuery = true)
public List<GsJsonStore> matchJson(String term, String value);
I'm testing the function using :
List<GsJsonStore> list = repo.matchJson("subject", "'Sub'");
The list is empty on running the query, however when I run the same query through PSQL command line using:
select * from gs where subject = 'Sub';
I get the correct output, records contatining the key-value pair are returned.
Where am I making the mistake?
You can't use parameter for column name. Your query resolves to
select * from gs where 'subject' = '''Sub'''
EDIT: just saw #pozs already posted the same in comment

Unable to query using 4 conditions with WHERE clause

I am trying to query a database to obtain rows that matches 4 conditions.
The code I'm using is the following:
$result = db_query("SELECT * FROM transportesgeneral WHERE CiudadOrigen LIKE '$origen%' AND DepartamentoOrigen LIKE '$origendep' AND DepartamentoDestino LIKE '$destinodep' AND CiudadDestino LIKE '$destino%'");
But it is not working; Nevertheless, when I try it using only 3 conditions; ie:
$result = db_query("SELECT * FROM transportesgeneral WHERE CiudadOrigen LIKE '$origen%' AND DepartamentoOrigen LIKE '$origendep' AND DepartamentoDestino LIKE '$destinodep'");
It does work. Any idea what I'm doing wrong? Or is it not possible at all?
Thank you so much for your clarification smozgur.
Apparently this was the problem:
I was trying to query the database by using the word that contained a tittle "Petén" so I changed the database info and replaced that word to the same one without the tittle "Peten" and it worked.
Now, im not sure why it does not accept the tittle but that was the problem.
If you have any ideas on how I can use the tittle, I would appreciate that very much.

How to use a dynamic parameter in a IN clause of a JPA named query?

my problem is about this kind of query :
select * from SOMETABLE where SOMEFIELD in ('STRING1','STRING2');
the previous code works fine within Sql Developer.
The same static query also works fine and returns me a few results;
Query nativeQuery = em.createNativeQuery(thePreviousQuery,new someResultSet());
return nativeQuery.getResultList();
But when I try to parameterize this, I encounter a problem.
final String parameterizedQuery = "select * from SOMETABLE where SOMEFIELD in (?selectedValues)";
Query nativeQuery = em.createNativeQuery(parameterizedQuery ,new someResultSet());
nativeQuery.setParameter("selectedValues","'STRING1','STRING2'");
return nativeQuery.getResultList();
I got no result (but no error in console).
And when I look at the log, I see such a thing :
select * from SOMETABLE where SOMEFIELD in (?)
bind => [STRING1,STRING2]
I also tried to use no quotes (with similar result), or non ordered parameter (:selectedValues), which leads to such an error :
SQL Error: Missing IN or OUT parameter at index:: 1
I enventually tried to had the parentheses set directly in the parameter, instead of the query, but this didn't work either...
I could build my query at runtime, to match the first (working) case, but I'd rather do it the proper way; thus, if anyone has an idea, I'll read them with great interest!
FYI :
JPA version 1.0
Oracle 11G
JPA support the use of a collection as a list literal parameter only in JPQL queries, not in native queries. Some JPA providers support it as a proprietary feature, but it's not part of the JPA specification (see https://stackoverflow.com/a/3145275/1285097).
Named parameters in native queries also aren't part of the JPA specification. Their behavior depends on the persistence provider and/or the JDBC driver.
Hibernate with the JDBC driver for Oracle support both of these features.
List<String> selectedValues = Arrays.asList("STRING1", "STRING2");
final String parameterizedQuery = "select * from SOMETABLE where SOMEFIELD in (:selectedValues)";
return em.createNativeQuery(parameterizedQuery)
.setParameter("selectedValues", selectedValues)
.getResultList();
Instead of:
nativeQuery.setParameter("selectedValues", params);
I had to use:
nativeQuery.setParameterList("selectedValues", params);
This worked for me in derby. parameter without "()".
List<String> selectedValues = Arrays.asList("STRING1", "STRING2");
final String parameterizedQuery = "select * from SOMETABLE where SOMEFIELD in
:selectedValues";
return em.createNativeQuery(parameterizedQuery)
.setParameter("selectedValues", selectedValues)
.getResultList();
Replace this:
nativeQuery.setParameter("selectedValues","'STRING1','STRING2'");
with
List<String> params;
nativeQuery.setParameter("selectedValues",params);
I also faced the same issue.
This is what I did:
List<String> sample = new ArrayList<String>();
sample.add("sample1");
sample.add("sample2");
And now you, can set the sample in params.

How to change sql generated by linq-to-entities?

I am querying a MS SQL database using Linq and Entity Framework Code First. The requirement is to be able to run a WHERE SomeColumn LIKE '%sometext'clause against the table.
This, on the surface, is a simple requirement that could be accomplished using a simple Linq query like this:
var results = new List<MyTable>();
using(var context = new MyContext())
{
results = context.MyTableQueryable
.Where(x => x.SomeColumn.EndsWith("sometext"))
.ToList();
}
// use results
However, this was not effective in practice. The problem seems to be that the column SomeColumn is not varchar, rather it's a char(31). This means that if a string is saved in the column that is less than 31 characters then there will be spaces added on the end of the string to ensure a length of 31 characters, and that fouls up the .EndsWith() query.
I used SQL Profiler to lookup the exact sql that was generated from the .EndsWith() method. Here is what I found:
--previous query code removed for brevity
WHERE [Extent1].[SomeColumn] LIKE N'%sometext'
So that is interesting. I'm not sure what the N means before '%sometext'. (I'll Google it later.) But I do know that if I take the same query and run it in SSMS without the N like this:
--previous query code removed for brevity
WHERE [Extent1].[SomeColumn] LIKE '%sometext'
Then the query works fine. Is there a way to get Linq and Entity Framework to drop that N from the query?
Please try this...
.Where(x => x.SomeColumn.Trim().EndsWith("sometext"))
Just spoke to my colleague who had a similar issue, see if the following works for you:
[Column(TypeName = "varchar")]
public string SomeColumn
{
get;
set;
}
Apparently setting the type on the column mapping will force the query to recognise it as a VARCHAR, where a string is normally interpreted as an NVARCHAR.