Skip to content
ClickHouse Docs
ClickHouse DocsClickHouse Docs
49.6kGet Started

external_table_* session settings

View as MarkdownEdit this pageReport an issueSet up docs MCP

These settings are available in system.settings and are autogenerated from source.

external_table_functions_use_nulls

Type
Bool
Default
1

Defines how mysql, postgresql and odbc table functions use Nullable columns.

Possible values:

  • 0 — The table function explicitly uses Nullable columns.
  • 1 — The table function implicitly uses Nullable columns.

Usage

If the setting is set to 0, the table function does not make Nullable columns and inserts default values instead of NULL. This is also applicable for NULL values inside arrays.

external_table_strict_query

Type
Bool
Default
0

If it is set to true, transforming expression to local filter is forbidden for queries to external tables.

Navigation