One of our customers is noticing that after applying CDH driver update v2.5.12, meta-store queries have become case-sensitive. In some cases, meta-store query returns right information only with table-names in lower-case while in some cases upper-case table-names work.
This behavior has never been observed before. As is standard with any database, schema-names/table-names/column-names have to be case-insensitive and so should be the meta query.
What exact metastore settings are causing this behavior? This urgently needs to be resolved. Please advice
Please bear in mind that there are 2 different JDBC drivers in the mix.
Cloudera Hive JDBC driver is used by Hive clients to connect to HiveServer2 (HS2). The Hive Metastore Server (HMS) uses the JDBC driver supplied by the vendor.
In any case, Hive follows the convention that database/tables names are case insensitive. Currently Hive is not SQL-92 compliant, but is moving in that direction.
Also be aware that in Hive table names and column names are case insensitive but SerDe and property names are case sensitive. ( https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL )