Method 'Boolean Equals(System.String, System.String, System.StringComparison)' is not supported for execution as SQL.

[emp51302]

Hi - I am trying to write a Linq query which looks like...

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MyDictionary word = bldc.MyDictionarys.FirstOrDefault(w => w.DicId == MyDicId && String.Equals(w.Word.Trim(), row[0].ToString().Trim(), StringComparison.OrdinalIgnoreCase));

But unfortunately I am getting

"Method 'Boolean Equals(System.String, System.String, System.StringComparison)' is not supported for execution as SQL."

Is there any other way to do a string compare in Linq for dotConnect.

Would appreciate it.

Thanks

[Shalex]

This method is currently not supported. We will post here when the corresponding support is implemented.

[Shalex]

As a temporary workaround, please use the following query:

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MyDictionary word = bldc.MyDictionarys.FirstOrDefault(w => w.DicId == MyDicId && (w.Word.Trim().ToLower() == row[0].ToString().Trim().ToLower()));

[emp51302]

Shalex - Already doing that, thanks! When will the requested functionality be available?

Thanks

[Shalex]

Tell us your opinion: what SQL should be generated for MySQL by String.Equals(stringExpression1, stringExpression2, stringComparisonValue) for different values of StringComparison?

We consider the most flexible way to do this with SQL-construction like

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stringExpression1 = stringExpression2 COLLATE x

where x is latin1_bin or utf16_bin or utf8_bin or any other collation.

So the Collate(string value, string collationName) method of the SqlMethods class is implemented in the new (7.8) version of dotConnect for MySQL.

An example of its usage:

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var a = context.Depts.FirstOrDefault<Dept>(w => w.DEPTNO == myDEPTNO && SqlMethods.Collate(w.DNAME.Trim(), "utf8_bin") == research.ToString().Trim());

The corresponding SQL would be:

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SELECT t1.DEPTNO, t1.DNAME, t1.LOC
FROM alexsh.Dept t1
WHERE (t1.DEPTNO = :p0) AND (TRIM(t1.DNAME) COLLATE 'utf8_bin' = :p1) LIMIT 1
-- p0: Input Int (Size = 0; DbType = Int32) [10]
-- p1: Input VarChar (Size = 8; DbType = AnsiString) [RESEARCH]