Fix limiting the number of threads for VIEW.

…um in CSV

…sed on a value

Enable CodeQL security scanner

Dockerfile security check for `clickhouse-server`

Improve REVOKE command

…threads

max_rows_to_read remove note about 'applied on each thread separately'

Exclude partition key columns from SummingMergeTree

Initial explain

Fix minor issues in ternary logic

Added performance test to resemble "questionable" benchmark

throw exception on redirect limit in S3 request

Polymorphic parts (in-memory format)

Added a test for PaddedPODArray just in case

Supertype for LowCardinality

Fix arrayFill for empty arrays.

…/20.5/12279

…f921a02c9290fd70e9e3d60f399c2

Cherry pick #12279 to 20.5: Fix arrayFill for empty arrays.