The join statements of the database can be used conveniently to perform the operation of alignment join. But sometimes the data is stored in the text files, and to compute it in Java alone we need to write a large number of loop statements. This makes the code cumbersome. Using esProc to help with programming in Java can solve the problem easily and quickly. Let’s look at how this works…

Program development for data process often involves cross-database relational operations. The following example will illustrate Java’s method of handling these operations. sales table is in db2 database, employee table is in mysql database. The task is to join sales with employee through sellerid of sales table and eid of employee table, and filter out the data insales and employeethat…

The computing power of SQL for mass structured data is complete, that is to say, it is impossible to find anything that SQL cannot compute. But its support layer is too low, which can lead to over-elaborate operation in practical application.…