Devart Forums

Posted: **Wed 26 Jan 2011 14:25**

I have a table, Metadata, with the columns:

Name: VARCHAR2(50)
Value: CLOB

When I execute the following query using Entity SQL,

var results = context.CreateQuery("SELECT VALUE m FROM Metadatas WHERE m.Value = 'Value1'").ToList();

I get the System.Data.EntityCommandExecutionException exception with the following error message: ORA-00932: inconsistent datatypes: expected - got CLOB

However, the following query works:

Code: Select all

var results = context.Metadatas.Where(x => x.Value == "Value1").ToList();

And this query also works:

Code: Select all

results = context.CreateQuery("SELECT VALUE m FROM Metadatas AS m WHERE m.Value = @v", new ObjectParameter("v", "Value1")).ToList();

I looked into DB Monitor to see what was going on, and I found that the first query (the error case) produced the following SQL:

Code: Select all

SELECT 
"Extent1".ID AS ID, 
"Extent1".NAME AS NAME, 
"Extent1".VALUE AS VALUE
FROM METADATA "Extent1"
WHERE "Extent1".VALUE = 'Value1'

The second query:

Code: Select all

SELECT 
"Extent1".ID AS ID, 
"Extent1".NAME AS NAME, 
"Extent1".VALUE AS VALUE
FROM METADATA "Extent1"
WHERE "Extent1".VALUE LIKE TO_CLOB('Value1')

The third query:

Code: Select all

SELECT 
"Extent1".ID AS ID, 
"Extent1".NAME AS NAME, 
"Extent1".VALUE AS VALUE
FROM METADATA "Extent1"
WHERE "Extent1".VALUE LIKE :v

It seems in the first case, there a bug where no special handling done for comparing CLOB values.

I am using Devart dotConnect for Oracle Professional 6.0.86.0.

Posted: **Wed 26 Jan 2011 15:41**

Thank you for the report, we have reproduced the error.
I will let you know about the result of our investigation.

Posted: **Thu 03 Mar 2011 14:06**

We have fixed this error. The fixed build will be available in a week or so.

Devart Forums

Bug Querying CLOB Columns using Entity SQL.

Bug Querying CLOB Columns using Entity SQL.