SQL on Hudi supports access to hudi tables stored on MRS. This function is supported only by clusters of version 9.1.0 or later.

Prerequisites

You have created an MRS data source. For details, see "MRS Data Sources" in Data Warehouse Service (DWS) User Guide.

SQL on Hudi can read hudi tables stored on MRS. The only difference in usage compared to OBS is when creating data sources.

Accessing Multiple MRS Clusters Concurrently

Due to JDK restrictions, one JVM can store only one Kerberos configuration file at a time. As a result, one GaussDB(DWS) cluster cannot concurrently access hudi tables in multiple MRS clusters through SQL on Hudi. To avoid this issue, do as follows:

Obtain the krb5.conf file of each MRS cluster from the downloaded client.
Use the krb5.conf file of any MRS cluster as the file to be combined (cluster A for short).

Add the KDC domain information of cluster B to realms in cluster A's configuration file.

Example:

[realms]
CLUSTER.A.COM = { 
admin_server =  ClusterA_SERVER_IP:PORT
kdc = ClusterA_KDC_IP:PORT
kdc = ClusterA_KDC_IP:PORT
} 
CLUSTER.B.COM = {
admin_server = ClusterB_SERVER_IP:PORT
kdc = ClusterB_KDC_IP:PORT
kdc = ClusterB_KDC_IP:PORT
}

Add the domain information of cluster B to domain_realm in cluster A's configuration file.
Example:
```
[domain_realm]
.cluster.a.com = CLUSTER.A.COM
.cluster.b.com = CLUSTER.B.COM
```
Replace the original krb5.conf file with the combined one in the original path of each node in each cluster.

The preceding example is for reference only. During actual operations, you need to combine the actual KDC domain information in the cluster' realms or domain_realm.

Accessing Hudi Tables on MRS

Prerequisites

Accessing Multiple MRS Clusters Concurrently