\begin{abstract_eng}
Haskell is a purely-functional programming language.
It provides a modern type system, type-safe and type inference makes it possible to write a program reliable\cite{types}.
Haskell has referential transparency that allows the programmer and the compiler to reason about program behavior.

In this study, we implement the parallel database using Haskell and non-destructive tree.

We measures the performance for reading and writing of parallel database.
We achieve to bring out the performance of the multi-core processor.

Further, in order to indicate the availability of practical applications, we have developed a Web bulletin board service.
\end{abstract_eng}