sql/statements/
set_variables.rs

1// Copyright 2023 Greptime Team
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use std::fmt::Display;
16
17use serde::Serialize;
18use sqlparser::ast::{Expr, ObjectName, ObjectNamePart, Value, ValueWithSpan};
19use sqlparser_derive::{Visit, VisitMut};
20
21/// SET variables statement.
22#[derive(Debug, Clone, PartialEq, Eq, Visit, VisitMut, Serialize)]
23pub struct SetVariables {
24    pub variable: ObjectName,
25    pub value: Vec<Expr>,
26}
27
28impl SetVariables {
29    /// Returns the first supported `search_path` value.
30    pub fn search_path(&self) -> Option<&str> {
31        let [ObjectNamePart::Identifier(variable)] = self.variable.0.as_slice() else {
32            return None;
33        };
34        if variable.quote_style.is_some() || !variable.value.eq_ignore_ascii_case("search_path") {
35            return None;
36        }
37
38        match self.value.first()? {
39            Expr::Value(ValueWithSpan {
40                value: Value::SingleQuotedString(value) | Value::DoubleQuotedString(value),
41                ..
42            }) => Some(value),
43            Expr::Identifier(value) => Some(&value.value),
44            _ => None,
45        }
46    }
47}
48
49impl Display for SetVariables {
50    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
51        let variable = &self.variable;
52        let value = &self
53            .value
54            .iter()
55            .map(|expr| format!("{}", expr))
56            .collect::<Vec<_>>()
57            .join(", ");
58
59        write!(f, r#"SET {variable} = {value}"#)
60    }
61}
62
63#[cfg(test)]
64mod tests {
65    use std::assert_matches;
66
67    use crate::dialect::GreptimeDbDialect;
68    use crate::parser::{ParseOptions, ParserContext};
69    use crate::statements::statement::Statement;
70
71    #[test]
72    fn test_display_show_variables() {
73        let sql = r"set delayed_insert_timeout=300;";
74        let stmts =
75            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default())
76                .unwrap();
77        assert_eq!(1, stmts.len());
78        assert_matches!(&stmts[0], Statement::SetVariables { .. });
79
80        match &stmts[0] {
81            Statement::SetVariables(set) => {
82                let new_sql = format!("\n{}", set);
83                assert_eq!(
84                    r#"
85SET delayed_insert_timeout = 300"#,
86                    &new_sql
87                );
88            }
89            _ => {
90                unreachable!();
91            }
92        }
93    }
94
95    #[test]
96    fn test_search_path() {
97        for (sql, expected) in [
98            ("SET search_path TO public", Some("public")),
99            ("SET SEARCH_PATH TO 'private'", Some("private")),
100            ("SET search_path TO \"quoted\"", Some("quoted")),
101            ("SET \"search_path\" TO private", None),
102            ("SET timezone TO 'UTC'", None),
103        ] {
104            let statements = ParserContext::create_with_dialect(
105                sql,
106                &GreptimeDbDialect {},
107                ParseOptions::default(),
108            )
109            .unwrap();
110            let [Statement::SetVariables(set)] = statements.as_slice() else {
111                unreachable!()
112            };
113            assert_eq!(expected, set.search_path());
114        }
115    }
116}
sql/statements/set_variables.rs

sql/statements/
set_variables.rs
