Submitted by: NoPyGod (nopygod)

Is duplicated by DNET514
Is related to DNET466
Relate to DNET518

Attachments:
Databases.zip
Setting.cs

With version 3.0.2.0, the following LINQ query

var isMaster = configDb.Settings.Where(x => x.Key == @"\ALPHA\ENVIRONMENT\MASTER").Single().Value == "1";

Was translated into

SELECT FIRST (2)
"B"."CONFIGKEY" AS "CONFIGKEY",
"B"."CONFIGVALUE" AS "CONFIGVALUE"
FROM "CONFIGURATION" AS "B"
WHERE _UTF8'\ALPHA\ENVIRONMENT\MASTER' = "B"."CONFIGKEY"

This works fine. Have been using the http://ADO.NET provider for months without any trouble

But today I tried to upgrade to version 3.1.0.0 of the provider, and now that same linq query is being translated into the SQL below

SELECT FIRST (2)
"B"."CONFIGKEY" AS "CONFIGKEY",
"B"."CONFIGVALUE" AS "CONFIGVALUE"
FROM "CONFIGURATION" AS "B"
WHERE CAST(_UTF8'\ALPHA\ENVIRONMENT\MASTER' AS VARCHAR(32765)) = "B"."CONFIGKEY"

Notice it now CASTs to VARCHAR(32765)

This unfortunately is giving an error:

Dynamic SQL Error
SQL error code = -204
Data type unknown
Implementation limit exceeded
COLUMN DSQL internal

I tried executing the same sql query outside of .NET, from IBExpert, and it also gives the same error there.

I have tried so many different things in IBExpert to get this to work but to no avail. I discovered that if I export the table structure and create a new database and import the structure into a new table, I can run the query without problems. I thought this might mean there was a problem with the database so I did the usual gfix, backup restore but that hasn't helped.

I've attached a zip containing two databases, one which works and the one which doesn't. Please try running this query to see the error I'm referring to --

SELECT *
FROM CONFIGURATION
WHERE CONFIGKEY = CAST(_UTF8'TEST' AS VARCHAR(32765))

I don't know if this is a problem with the http://ADO.NET provider or with the Firebird engine itself, but since 3.0.2.0 worked and 3.1.0.0 doesn't I thought I'd report it here.

Commits: ecb9fb1