Hi,
My use case is to optimize certain aggregation queries in a very large
and flat table.
The table schema would be like below:
EmployeeID , DepartmentID, <Employee Details ...> < Department Details
...> <Company details >
Most of my queries are "group by" over <EmployeeID, DepartmentID>, and
nested as:
select ... ( select ... group by EmployeeID ) ... group by EmployeeID,
DepartmentID
>From my basic Ignite understanding, keeping the EmployeeID,
DepartmentID co-located would help in query performance, assuming a
EmpoyeeID is always linked to a single DepartmentID, I tried the
following:
1. created AffinityKey<EmployeeID, DepartmentID> in the pojo
public class Model implements Serializable{
@QuerySqlField(index = true)
private String employeeID;
@QuerySqlField(index = true)
private String departmentID;
...
public AffinityKey<String> key() {
if (key == null)
key = new AffinityKey<>(employeeID, employeeID);
return key;
}
...
}
2. used DataStreamer to load cache as follow (inspired by
CacheQueryExample.initialize):
CacheConfiguration<AffinityKey<String>, Model> cacheConfiguration =
new CacheConfiguration<>(CACHE_NAME);
cacheConfiguration.setCacheMode(CacheMode.PARTITIONED);
cacheConfiguration.setIndexedTypes(AffinityKey.class, Model.class);
try (IgniteCache<AffinityKey<String>, Model> cache =
ignite.getOrCreateCache(cacheConfiguration)) {
try (IgniteDataStreamer<AffinityKey<String>, Model> stmr =
ignite.dataStreamer(CACHE_NAME)) {
...
Model model = new Model();
...
stmr.addData(model.key(), model);
...
I am doing it wrong here as I get only one record per key (EmployeeID,
DepartmentID) in the cache when I load the data.
Could you please let me know the correct usage of the AffinityKey to
achieve co-location , or if I need to try out other ways for it.
Regards,
Moiz
PS: ... used to hide some relevant code
