> ## Documentation Index
> Fetch the complete documentation index at: https://clickhouse.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# ignore_* session settings
> ClickHouse session settings in the ignore_* generated group.
export const SettingsInfoBlock = ({type, default_value, changeable_without_restart}) => {
return
Type
{type}
Default
{default_value}
{changeable_without_restart &&
Changeable without restart
}
{changeable_without_restart &&
{changeable_without_restart}
}
;
};
export const CloudOnlyBadge = () => {
return
{'ClickHouse Cloud only'}
;
};
These settings are available in [system.settings](/docs/reference/system-tables/settings) and are autogenerated from [source](https://github.com/ClickHouse/ClickHouse/blob/master/src/Core/Settings.cpp).
ignore\_cold\_parts\_seconds
Only has an effect in ClickHouse Cloud. Exclude new data parts from SELECT queries until they're either pre-warmed (see [cache\_populated\_by\_fetch](/docs/reference/settings/merge-tree-settings#cache_populated_by_fetch)) or this many seconds old. Only for Replicated-/SharedMergeTree.
ignore\_data\_skipping\_indices
Ignores the skipping indexes specified if used by the query.
Consider the following example:
```sql theme={null}
CREATE TABLE data
(
key Int,
x Int,
y Int,
INDEX x_idx x TYPE minmax GRANULARITY 1,
INDEX y_idx y TYPE minmax GRANULARITY 1,
INDEX xy_idx (x,y) TYPE minmax GRANULARITY 1
)
Engine=MergeTree()
ORDER BY key;
INSERT INTO data VALUES (1, 2, 3);
SELECT * FROM data;
SELECT * FROM data SETTINGS ignore_data_skipping_indices=''; -- query will produce CANNOT_PARSE_TEXT error.
SELECT * FROM data SETTINGS ignore_data_skipping_indices='x_idx'; -- Ok.
SELECT * FROM data SETTINGS ignore_data_skipping_indices='na_idx'; -- Ok.
SELECT * FROM data WHERE x = 1 AND y = 1 SETTINGS ignore_data_skipping_indices='xy_idx',force_data_skipping_indices='xy_idx' ; -- query will produce INDEX_NOT_USED error, since xy_idx is explicitly ignored.
SELECT * FROM data WHERE x = 1 AND y = 2 SETTINGS ignore_data_skipping_indices='xy_idx';
```
The query without ignoring any indexes:
```sql theme={null}
EXPLAIN indexes = 1 SELECT * FROM data WHERE x = 1 AND y = 2;
Expression ((Projection + Before ORDER BY))
Filter (WHERE)
ReadFromMergeTree (default.data)
Indexes:
PrimaryKey
Condition: true
Parts: 1/1
Granules: 1/1
Skip
Name: x_idx
Description: minmax GRANULARITY 1
Parts: 0/1
Granules: 0/1
Skip
Name: y_idx
Description: minmax GRANULARITY 1
Parts: 0/0
Granules: 0/0
Skip
Name: xy_idx
Description: minmax GRANULARITY 1
Parts: 0/0
Granules: 0/0
```
Ignoring the `xy_idx` index:
```sql theme={null}
EXPLAIN indexes = 1 SELECT * FROM data WHERE x = 1 AND y = 2 SETTINGS ignore_data_skipping_indices='xy_idx';
Expression ((Projection + Before ORDER BY))
Filter (WHERE)
ReadFromMergeTree (default.data)
Indexes:
PrimaryKey
Condition: true
Parts: 1/1
Granules: 1/1
Skip
Name: x_idx
Description: minmax GRANULARITY 1
Parts: 0/1
Granules: 0/1
Skip
Name: y_idx
Description: minmax GRANULARITY 1
Parts: 0/0
Granules: 0/0
```
Works with tables in the MergeTree family.
ignore\_drop\_queries\_probability
If enabled, server will ignore all DROP table queries with specified probability (for Memory and JOIN engines it will replace DROP to TRUNCATE). Used for testing purposes
ignore\_format\_null\_for\_explain
If enabled, `FORMAT Null` will be ignored for `EXPLAIN` queries and default output format will be used instead.
When disabled, `EXPLAIN` queries with `FORMAT Null` will produce no output (backward compatible behavior).