From b16e801fb4cc100ea69ae5be7ddbaeeef7b2d117 Mon Sep 17 00:00:00 2001 From: Maksim Kita Date: Sat, 12 Jun 2021 18:42:00 +0300 Subject: [PATCH] Added update_lag option documentation --- .../external-dictionaries/external-dicts-dict-lifetime.md | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md b/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md index 4c096d98042..e339461e428 100644 --- a/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md +++ b/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md @@ -94,6 +94,8 @@ It is also possible for `Flat`, `Hashed`, `ComplexKeyHashed` dictionaries to onl - If source is Executable then `update_field` will be added as executable script argument with last update time as argument value. - If source is ClickHouse, MySQL, PostgreSQL, ODBC there will be additional part of WHERE, where `update_field` is compared as greater or equal with last update time. +If `update_field` option is set. Additional option `update_lag` can be set. Value of `update_lag` option is subtracted from previous update time before request updated data. + Example of settings: ``` xml @@ -102,6 +104,7 @@ Example of settings: ... added_time + 15 ... @@ -111,6 +114,6 @@ or ``` sql ... -SOURCE(CLICKHOUSE(... update_field 'added_time')) +SOURCE(CLICKHOUSE(... update_field 'added_time' update_lag 15)) ... ``` \ No newline at end of file