We will see how to write simple ‘Select’ queries with Where clause in Hive. Hive Table We have a table ‘Employee’ in Hive with the following schema. 0: jdbc:hive2://localhost:10000> desc Employee; +————-+————+———-+–+ | col_name | data_type | comment | +————-+————+———-+–+ | id | bigint | | | name | string …
Basics We will see how to execute a simple SQL SELECT query in Java using JDBC Statement. Step 1 – Load Driver Class For connecting to the database we need to have a suitable Driver class loaded. This Driver class helps us to get the Connection to the corresponding database.…
Problem Statement :- While working on one of the project, we came across the following requirement:- Given a list of unique IDs, check whether for each ID the data is exactly the same in the database tables of two different systems. For non-matching data dump the unique ID in a…
Sometimes our application needs to fetch a large amount of data from database systems and do some in memory processing on top of it. The SELECT query to fetch the data may contain a WHERE clause, IN operator etc and the query may return millions of rows. Our application and…