Problemsby GlyphTrouble with ClickHouse database
6 posts from 2 people5d activeRising, +3 this week
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The posts behind it
A refused `DROP DATABASE` or `DETACH DATABASE` stops the replication of a `Replicated` or `MaterializedPostgreSQL` database
### Describe what's wrong `InterpreterDropQuery::executeToDatabaseImpl` calls `database->stopReplication()` for every database with `hasReplicationThread` (`DatabaseReplicated`, `DatabaseMaterializedPostgreSQL`) before it goes through the tables...
MySQLDump format rejects dumps starting with CREATE DATABASE
...there are no INSERT queries and suggests an explicit structure, which also fails. - Workaround is setting `input_format_mysql_dump_table_name`, but that defeats normal dump loading. Root cause: In `MySQLDumpRowInputFormat::skipToInsertOrCreateQuery`, the `continue` inside the...
`Filesystem` database rejects all tables when `user_files_path` is a symlink
...the same path. - Actual: no spelling of the path succeeds, so the `Filesystem` engine is unusable whenever the data directory is relocated via a symlink. Root cause: `checkTableFilePath` in `DatabaseFilesystem.cpp:134-140` compares the table path against the raw, uncanonicalized...
`DROP NAMED COLLECTION` succeeds while a database uses the collection, and the server then fails to start
### Describe what's wrong Since https://github.com/ClickHouse/ClickHouse/issues/77366, `DROP NAMED COLLECTION` refuses to drop a collection that a table uses (`NAMED_COLLECTION_IS_USED`): a table registers itself as a dependent of its collection...
A database `SETTINGS unknown_name = DEFAULT` is accepted and stored
### Describe what's wrong `CREATE DATABASE ... SETTINGS` rejects an unknown setting written as `name = value` (`UNKNOWN_SETTING`), but accepts the same name written as `name = DEFAULT`, and stores it in the database's definition, where it stays after a restart. A typo in a reset...
SYSTEM DROP DATABASE REPLICA ... FROM ZKPATH formatter drops WITH TABLES
### Describe what's wrong - EXPLAIN SYNTAX, formatQuery and clickhouse-format silently strip the WITH TABLES clause. - Trigger: SYSTEM DROP DATABASE REPLICA with FROM ZKPATH and WITH TABLES. - Expected output keeps WITH TABLES; actual output omits it. - Running the reformatted...
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About this problem
Evidence
6 posts from 2 people in 1 place, about 2 a week over 23 days. Mostly on ClickHouse/ClickHouse. Tools named alongside: GitHub, PostgreSQL, MySQL, Docker.
Frustration Frustration 1 of 3· Seen on GitHub issues
How it was grouped
Posts about ClickHouse with no known issue, sharing the word "database". First post Oct 4, 2026, latest Oct 26, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method
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History