The session is the users session, not the drill bit. Since you are connected to a specific drill bit, when you alter session it will work. Try to use session stickiness or pinning on your HA solution and you will be go. With my DNS round robin it picks a "connecting" drill bit and sticks to it until the session is done. The settings apply to the drill cluster while in distributed mode.
On Tue, Sep 4, 2018 at 3:56 PM, Joe Auty <j...@thinkdataworks.com> wrote: > Thanks for your response John! > > We are using Drill both in an ETL context, as well as for general > warehouse queries. One Drill user uses store format set to Parquet while > the other uses store format set to CSV to read and write from HDFS. We are > currently using Kubernetes Services rather than DNS round robin, but we > only have one drillbit in the cluster while we try to sort out this issue. > > I'm not clear though how alter session would work with a session with > multiple drillbits involved? We need to ensure that the right store format > option is set, so like I said we are using different Drill usernames and > sessions to accommodate this, but how would alter session commands apply to > preserve these different settings across multiple drillbits? > > > > > > > John Omernik wrote on 2018-09-04 2:48 PM: > >> Are these ETL ish type queries? store.format should only apply when Drill >> is writing data, when it is reading, it uses the filenames and other hints >> to read. >> >> Thus, if you do HA, say with DNS (like like in the other thread) and prior >> to running your CREATE TABLE AS (I Am assuming this is what you are doing) >> you can do ALTER SESSION set store.format = 'parquet' >> >> Instead of setting the ALTER SYSTEM, you can use ALTER SESSION so it only >> applies to the current session, regardless of foreman. >> >> John >> >> >> On Tue, Sep 4, 2018 at 1:00 PM, Joe Auty <j...@thinkdataworks.com> wrote: >> >> Hello, >>> >>> We need to have some queries executed with store.format set to parquet >>> and >>> some with this option set to CSV. To date we have experimented with >>> setting >>> the store format for sessions controlled by using two separate user >>> logins >>> as a sort of context switch, but I'm wondering if the group here might >>> have >>> suggestions for a better way to handle this, particularly one that will >>> scale a little better for us? >>> >>> The main problem we have with this approach is in introducing multiple >>> drillbits/HA and assuring that the session and the settings we need are >>> respected across all drillbits (whether with an HAProxy + sticky session >>> approach or any other approach). There is a more general thread (which >>> I've >>> chosen not to hijack) about HA Drill from a more general standpoint, you >>> might think of my question here as being similar, but with the need for a >>> context switch to support multiple Drill configurations/session options. >>> >>> Here are the various attempts and approaches we have come up with so far. >>> I'm wondering if you'd have any general advice as to which approach would >>> be best for us to take, considering future plans for Drill itself. For >>> example, if need be we can write our own plugin(s) if this is the >>> smartest >>> approach: >>> >>> - embedded the store.format option into the query itself by chaining >>> multiple queries together separated by a comma (it appears that this >>> doesn't work at all) >>> - look into writing some sort of plugin to allow us to scale our current >>> approach somehow (I realize that this is vague) >>> - a "foreman" approach where we stick with our current approach and >>> direct >>> all requests to our "foreman"/master with the hope and expectation that >>> it >>> will farm out work to the workers/slaves >>> - multiple clusters set with different settings >>> >>> Each of these approaches seems to have its pros and cons. To reiterate: >>> what approach do you think would be the smartest and most future-proof >>> approach for us to take? >>> >>> Thanks in advance! >>> >>> >
