The background is described in this issue: #15723,
where users used Apache Druid to satisfy such lambada requirements before.
We will not make Doris dropping data not belonged to current time window automatically like Druid,
which is not flexible. We demand a ability to support mutable/immutable partition, the PR works this way:
1. Support mutable property for a partition.
2. The mutable property of a partition is passed from FE to BE in a load procedure
3. If a record's partition is immutable, we mark this row as "un selected" which will not be included in computation of 'max_filter_ratio',
so that data write to immutable partition will be neglected and not cause load failure.
Use Example:
1. Add immutable partition or modify an partition to be immutable:
- alter table test_tbl add [temporary] partition xxx values less than ('xxx') ('mutable' = 'true');
- alter table test_tbl modify partition xx set ('mutable' = 'false');
2. Write 5 records into table, two of then belongs to immutable partition
e2e6a0dd83