Use Spark to dump SQL tables into Parquet files (locally or on HDFS).
As of Spark 1.5(?), use JDBCRDD: https://github.com/apache/spark/blob/master/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JDBCRDD.scala
E.g.
sqlContext
.read.jdbc(url, "table", properties)
.write.parquet("/path/to/output")