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by Jiří {x2} Činčura

Binding Boolean fields from Firebird

2 Jul 2007 1 mins .NET, Firebird

From time to time there’s a question about binding bool fields from Firebird into DataSet/DataTable. Because Firebird has no bool datatype people created a lot of workarounds. The most used way is to use CHAR(1) or SMALLINT as base type (or domain with check constraint). With integer, there’s no problem. When you have 0/1 False/True it’s trivial. But how to do this with char (or any other way you’re using). Well, the solution is easy. I like this one.

I create select, that returns true/false as 1/0 directly. Using CASE statement is really helpful. This solution has minimal overhead and can be used with any datatype you’re using as bool. For fine-tunning you can create a view or stored procedure (for select or only for returning 0/1 values from your type).

IMO this solution pretty easy and straightforward. You can use it with Fb… objects directly or with DDEX generated without any problem.

Profile Picture Jiří Činčura is an independent developer, .NET, C# and Firebird expert, focusing on data and business layers, language constructs, parallelism, databases and performance. He's Microsoft Most Valuable Professional and frequent speaker. You can read his articles, guides and tips and tricks at