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Merge branch 'master' of github.com:yandex/ClickHouse
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@ -45,7 +45,10 @@ CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]
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[SETTINGS name=value, ...]
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[SETTINGS name=value, ...]
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```
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```
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For descriptions of request parameters, see the [request description](../../query_language/create.md).
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For a description of parameters, see the [CREATE query description](../../query_language/create.md).
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!!! note "Note"
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`INDEX` is an experimental feature, see [Data Skipping Indexes](#table_engine-mergetree-data_skipping-indexes).
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### Query Clauses
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### Query Clauses
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@ -236,7 +239,7 @@ ClickHouse cannot use an index if the values of the primary key in the query par
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ClickHouse uses this logic not only for days of the month sequences, but for any primary key that represents a partially-monotonic sequence.
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ClickHouse uses this logic not only for days of the month sequences, but for any primary key that represents a partially-monotonic sequence.
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### Data Skipping Indices (Experimental)
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### Data Skipping Indexes (Experimental) {#table_engine-mergetree-data_skipping-indexes}
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You need to set `allow_experimental_data_skipping_indices` to 1 to use indices. (run `SET allow_experimental_data_skipping_indices = 1`).
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You need to set `allow_experimental_data_skipping_indices` to 1 to use indices. (run `SET allow_experimental_data_skipping_indices = 1`).
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@ -295,6 +298,14 @@ SELECT count() FROM table WHERE u64 * i32 == 10 AND u64 * length(s) >= 1234
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The same as `ngrambf_v1`, but stores tokens instead of ngrams. Tokens are sequences separated by non-alphanumeric characters.
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The same as `ngrambf_v1`, but stores tokens instead of ngrams. Tokens are sequences separated by non-alphanumeric characters.
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- `bloom_filter([false_positive])` — Stores [bloom filter](https://en.wikipedia.org/wiki/Bloom_filter) for the specified columns.
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The `false_positive` optional parameter is the probability of false positive response from the filter. Possible values: (0, 1). Default value: 0.025.
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Supported data types: `Int*`, `UInt*`, `Float*`, `Enum`, `Date`, `DateTime`, `String`, `FixedString`.
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Supported for the following functions: [equals](../../query_language/functions/comparison_functions.md), [notEquals](../../query_language/functions/comparison_functions.md), [in](../../query_language/functions/in_functions.md), [notIn](../../query_language/functions/in_functions.md).
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```sql
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```sql
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INDEX sample_index (u64 * length(s)) TYPE minmax GRANULARITY 4
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INDEX sample_index (u64 * length(s)) TYPE minmax GRANULARITY 4
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INDEX sample_index2 (u64 * length(str), i32 + f64 * 100, date, str) TYPE set(100) GRANULARITY 4
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INDEX sample_index2 (u64 * length(str), i32 + f64 * 100, date, str) TYPE set(100) GRANULARITY 4
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