ClickHouse / ClickHouse/ClickHouse
Dropping column not allowed because it is referenced in a materialized view, which isn't true (although a CTE with the same column name exists)
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Description
### Company or project name
_No response_
### Describe what's wrong
I'm trying to drop a column `val` from a source table that has an MV attached.
The MV uses a CTE that selects a _constant value_ as `val`, but doesn't read the `val` in the source table.
I think this should allow me to drop `val` from the source table, but this results in a `Trying to ALTER DROP column val which is referenced by materialized view ['dest_mv']` error.
Without the CTE it works correctly.
I know the example looks quite pointless. The actual case where I encountered this behaviour is in the down script for a migration that added the `val` column to the source table, while the previous version of the code was using `now()` as a default.
### Does it reproduce on the most recent release?
Yes
### How to reproduce
See [fiddle](https://fiddle.clickhouse.com/5a00a98a-2a24-41a8-9888-ff791a673bf4)
### Expected behavior
The `val` column should be dropped since the MV doesn't use it.
### Error message and/or stacktrace
_No response_
### Additional context
_No response_
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