sqlparser/dialect/
clickhouse.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18use crate::dialect::Dialect;
19
20/// A [`Dialect`] for [ClickHouse](https://clickhouse.com/).
21#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
22#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
23pub struct ClickHouseDialect {}
24
25impl Dialect for ClickHouseDialect {
26    fn is_identifier_start(&self, ch: char) -> bool {
27        // See https://clickhouse.com/docs/en/sql-reference/syntax/#syntax-identifiers
28        ch.is_ascii_lowercase() || ch.is_ascii_uppercase() || ch == '_'
29    }
30
31    fn is_identifier_part(&self, ch: char) -> bool {
32        self.is_identifier_start(ch) || ch.is_ascii_digit()
33    }
34
35    /// ClickHouse accepts both backticks and double quotes, but its own
36    /// formatter emits backticks by default.
37    /// See <https://clickhouse.com/docs/en/sql-reference/syntax#identifiers>
38    fn identifier_quote_style(&self, _identifier: &str) -> Option<char> {
39        Some('`')
40    }
41
42    fn supports_string_literal_backslash_escape(&self) -> bool {
43        true
44    }
45
46    fn supports_select_wildcard_except(&self) -> bool {
47        true
48    }
49
50    fn describe_requires_table_keyword(&self) -> bool {
51        true
52    }
53
54    fn require_interval_qualifier(&self) -> bool {
55        true
56    }
57
58    fn supports_limit_comma(&self) -> bool {
59        true
60    }
61
62    fn supports_insert_table_function(&self) -> bool {
63        true
64    }
65
66    fn supports_insert_format(&self) -> bool {
67        true
68    }
69
70    fn supports_numeric_literal_underscores(&self) -> bool {
71        true
72    }
73
74    fn supports_partition_by_after_order_by(&self) -> bool {
75        true
76    }
77
78    fn supports_array_join_syntax(&self) -> bool {
79        true
80    }
81
82    // ClickHouse uses this for some FORMAT expressions in `INSERT` context, e.g. when inserting
83    // with FORMAT JSONEachRow a raw JSON key-value expression is valid and expected.
84    //
85    // [ClickHouse formats](https://clickhouse.com/docs/en/interfaces/formats)
86    fn supports_dictionary_syntax(&self) -> bool {
87        true
88    }
89
90    // See <https://clickhouse.com/docs/sql-reference/operators/in>
91    fn supports_in_unparenthesized_expr(&self) -> bool {
92        true
93    }
94
95    /// See <https://clickhouse.com/docs/en/sql-reference/functions#higher-order-functions---operator-and-lambdaparams-expr-function>
96    fn supports_lambda_functions(&self) -> bool {
97        true
98    }
99
100    fn supports_from_first_select(&self) -> bool {
101        true
102    }
103
104    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by>
105    fn supports_order_by_all(&self) -> bool {
106        true
107    }
108
109    // See <https://clickhouse.com/docs/en/sql-reference/aggregate-functions/grouping_function#grouping-sets>
110    fn supports_group_by_expr(&self) -> bool {
111        true
112    }
113
114    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/group-by#rollup-modifier>
115    fn supports_group_by_with_modifier(&self) -> bool {
116        true
117    }
118
119    /// Supported since 2020.
120    /// See <https://clickhouse.com/docs/whats-new/changelog/2020#backward-incompatible-change-2>
121    fn supports_nested_comments(&self) -> bool {
122        true
123    }
124
125    /// See <https://clickhouse.com/docs/en/sql-reference/statements/optimize>
126    fn supports_optimize_table(&self) -> bool {
127        true
128    }
129
130    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/prewhere>
131    fn supports_prewhere(&self) -> bool {
132        true
133    }
134
135    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by#order-by-expr-with-fill-modifier>
136    fn supports_with_fill(&self) -> bool {
137        true
138    }
139
140    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/limit-by>
141    fn supports_limit_by(&self) -> bool {
142        true
143    }
144
145    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by#order-by-expr-with-fill-modifier>
146    fn supports_interpolate(&self) -> bool {
147        true
148    }
149
150    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select#settings-in-select-query>
151    fn supports_settings(&self) -> bool {
152        true
153    }
154
155    /// See <https://clickhouse.com/docs/en/sql-reference/statements/select/format>
156    fn supports_select_format(&self) -> bool {
157        true
158    }
159
160    /// See <https://clickhouse.com/docs/sql-reference/statements/select#replace>
161    fn supports_select_wildcard_replace(&self) -> bool {
162        true
163    }
164
165    fn supports_comma_separated_trim(&self) -> bool {
166        true
167    }
168}
sqlparser/dialect/clickhouse.rs

sqlparser/dialect/
clickhouse.rs
