CRUD Operations In Postgres Using C#

public string ConnectionString { 
    get { 
        return@"Provider=PostgreSQL OLE DB Provider;Server=127.0.0.1; 
Database=<db_name>;User ID=<user_name>;password=<password>;"; 
    } 
} 

public DataTable GetResultSetTable(string query) { 
    DataTable table = new DataTable(); 
    using(NpgsqlConnection connection = new NpgsqlConnection(ConnectionString)) { 
        connection.Open(); 
        using(NpgsqlCommand command = new NpgsqlCommand(query, connection)) { 
            using(NpgsqlDataAdapter adapter = new NpgsqlDataAdapter()) { 
                adapter.SelectCommand = command; 
                adapter.Fill(table); 
            } 
        } 
    } 
    return table; 
} 

public void ExecuteQuery(string query) { 
    using(NpgsqlConnection connection = new NpgsqlConnection(ConnectionString)) { 
        connection.Open(); 
        using(NpgsqlCommand command = new NpgsqlCommand(query, connection)) { 
            command.ExecuteNonQuery(); 
        } 
    } 
} 

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