Set Empty Fields to Null in Hive

Depending on the data you load into Hive/HDFS, some of your fields might be empty. Having Hive interpret those empty fields as nulls can be very convenient. It is easy to do this in the table definition using the serialization.null.format table property. Here is a an example from the Big Datums GitHub repo :

Get Input File name in Hive Query

Often times it is useful to know the input file name you are processing in a Hive query. This is a common if useful metadata is stored in the file name. For example, logs from many different servers can be stored in S3, and these files’ names could contain the names or ip addresses of

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