Below is a table queried from BigQuery database. Its 4th field has comma-separated strings.

Use Java to do this: Retain the first 3 fields, split values the 4th field, make the distinct values names of the fields from 4th to Nth, write 1 or 0 under each new field to record whether they are originally included in the current row or not, and save result as a new file. Below is the expected result:

Write SPL code as follows:

A1: Query the database through JDBC.

A2: Split up each value of the 4th field and generate a record for each distinct value; ~ is the current item.

A3: Perform row-to-column transposition – retain the first 3 columns, transform values of the 4th column to the new field names, and write 1 under each new field if they are included in the current row in the original table and 0 if they are not.

A4: Write result to a csv file.

Read How to Call a SPL Script in Java to find how to integrate SPL into a Java application.

This is one of the problems on StackOverflow. You can click on it to see that the conventional solution is quite complicated, but the SPL approach is really simple and efficient.

SPL open source address