CREATE MAPPING
You create a mapping that automatically routes queries to a specific pool using this command.
CREATE MAPPING syntax
CREATE { USER | GROUP | APPLICATION } MAPPING 'entity_name' IN plan_name { TO pool_path | UNMANAGED } [ WITH ORDER num ]
- entity_name
A JDBC connection user, group of JDBC connection users, or JDBC application name
- plan_name
The resource plan name
- pool_path
The hierarchy of query pool names, in dot notation
- num
An integer
CREATE MAPPING examples
CREATE GROUP MAPPING 'students' IN rp1 TO pool1 WITH ORDER 1
CREATE GROUP MAPPING 'teachers' IN rp1 TO pool2 WITH ORDER 3
CREATE APPLICATION MAPPING 'app1' IN rp1 TO pool3 WITH ORDER 2- Queries from users in group students go to pool1.
- Users using app1 go to pool2, unless they are in group students.
- Users in group teacher go to pool3, unless they are also in group students or are using app1.
- Users that are not in students or teachers and that are not using application app1 go to pool4.
CREATE MAPPING description
You can create a mapping based on a user, a group, or an application identified by the entity name. Mapping user, group, or application entities to a pool routes queries from those entities to the pool. The queries in the pool are under workload management.
User or group mapping
As administrator, you can configure valid non-application mapping for a particular user or
group. The pool must exist. Alternatively, you can set
hive.server2.wm.allow.any.pool.via.jdbc to true. For example, users in
two different groups, each mapped to a separate pool, can explicitly submit queries to
either of the pools regardless of the priority of the corresponding mappings that apply.
Workload management bases authorization to fetch a group or user on the HDFS group configuration on the cluster. By default, these are Apache Hadoop users and groups, but you can configure Lightweight Directory Protocol (LDAP) and other mechanisms.
Application mapping
To create a mapping based on an application, you use one of the following designations:
- The
applicationNameproperty in the JDBC connection string -
using the SetClientInfo JDBC API with the
ApplicationNamekey.
To
configure explicit querying of any pool, use multiple mappings through the
wmPool property in the JDBC connection string.
Unmanaged queries
Queries from users, groups, or applications not mapped to a pool are unmanaged. The queries are not under workload management.
Ordered rules
The optional WITH ORDER clause establishes the priorities for the rules. If multiple rules apply (for example, a user rule and a group rule, or multiple groups), the lowest ordered rule takes precedence. If ordering is not specified (or is the same), user rules take precedence over application rules, which take precedence over group rules. The order of group rules with the same priority is undefined.