I have an HIVE table with daily partitions day wise, something like below (which includes future date's partition as well)
20160901
20160902
........
........
........
20160931
20161001
20161002
I want to pass one date say for example yesterday's date 20160922 and want to drop all partitions dynamically which are >= 20160922 (though today is 20160923, but I want to drop from 20160922 date).
How can I can drop all these partitions dynamically.
You can not do in hive directly as it does not support dynamic sql.
There can be work around using shell script/or any script create file having drop partition script like below.
alter table partition_t drop if exists partition (y=20160922 );
alter table partition_t drop if exists partition (y=20160921 );
alter table partition_t drop if exists partition (y=20160920 ); ...
then run hive -v -f ./file.sh
alter table partition_t drop if exists partition
Before Inserting Data Into Table Perform the below steps.
1) Go to Hdfs Folder of that table and delete all the folders Inside Table Directory using Shell Commands. hadoop fs -rm r <>
2) Run MSCK repair Table to update the metadata about partitions.
above two steps will delete all the available partitions based on pattern.
Now Insert your new data.
You can drop partitions giving a range filter. For reference see that answer : https://stackoverflow.com/a/48422251/3132181 So your code could be like that:
Alter table mytable drop partition (datehour >= '20160922')
