arina-ielchiieva edited a comment on issue #1711: DRILL-7011: Support schema in scan framework URL: https://github.com/apache/drill/pull/1711#issuecomment-476166889 @paul-rogers Actually when I was presenting the schema provisioning design, there were a proposal to add schema property `drill.is_full_schema`. By default it’s `false`, thus we assume that schema is partial. If user wants to indicate that schema is strict and to ignore all columns except of those indicated in schema, he needs to create schema the following way: `create schema (col int) for table dfs.tmp.t. properties ('drill.is_full_schema' = 'true')` Since most of the `default` property problems are related to star queries, we can state the following: 1. For queries with defined list of columns (aka projection queries: `select id, name from t`), we apply schema consistently. 2. For star queries and when schema property `drill.is_full_schema` is set to `false`, we might get inconsistent results with default values but it's ok since we discover schema on the read. 3. For star queries and when schema property `drill.is_full_schema` is set to `true`, we project only those columns indicated in schema. What do you think?
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