How do production Cassandra DBA's do table changes & additions? -

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i interested in how cassandra production dba's processes change when using cassandra , performing many releases on year. during releases, columns in tables change , number of cassandra tables, new features , queries supported.

in relational db, in production, create 'view' , boom data there - loaded view's query.

with cassandra, dba have create new cassandra table , have write/run script copy required data table? can production level cassandra dba provide pointers on processes?

we run small shop, can tell how manage table/keyspace changes, , may differ how others done. first, keep text .cql file in our (private) git repository has of our tables , keyspaces in current formats. when changes made, update file. lets other developers know current tables like, without having use ssh or devcenter. has added advantage of giving file allows restore our schema single command.

if it's small change (like adding new column) i'll try out there prior deploying our application code. if it's new table, may create earlier, new table without code use doesn't hurt anything.

however, if significant change...such updating/removing existing column or changing key...i create new table. way, can deploy our code use new table(s), , nobody ever knows switched behind scenes. obviously, if table needs have data in it, i'll have export/import scripts ready ahead of time , run right after deploy.

larger corporations enterprise deployments use tools chef manage schema deployments. when have large number of nodes or clusters, automated deployment tool best way go.


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