sql/statements/
describe.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
// Copyright 2023 Greptime Team
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use std::fmt::Display;

use sqlparser::ast::ObjectName;
use sqlparser_derive::{Visit, VisitMut};

/// SQL structure for `DESCRIBE TABLE`.
#[derive(Debug, Clone, PartialEq, Eq, Visit, VisitMut)]
pub struct DescribeTable {
    name: ObjectName,
}

impl DescribeTable {
    /// Creates a statement for `DESCRIBE TABLE`
    pub fn new(name: ObjectName) -> Self {
        Self { name }
    }

    pub fn name(&self) -> &ObjectName {
        &self.name
    }
}

impl Display for DescribeTable {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let name = self.name();
        write!(f, r#"DESCRIBE TABLE {name}"#)
    }
}

#[cfg(test)]
mod tests {
    use std::assert_matches::assert_matches;

    use crate::dialect::GreptimeDbDialect;
    use crate::parser::{ParseOptions, ParserContext};
    use crate::statements::statement::Statement;
    use crate::util::format_raw_object_name;

    #[test]
    pub fn test_describe_table() {
        let sql = "DESCRIBE TABLE test";
        let stmts: Vec<Statement> =
            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default())
                .unwrap();
        assert_eq!(1, stmts.len());
        assert_matches!(&stmts[0], Statement::DescribeTable { .. });
        match &stmts[0] {
            Statement::DescribeTable(show) => {
                assert_eq!(format_raw_object_name(&show.name), "test");
            }
            _ => {
                unreachable!();
            }
        }
    }

    #[test]
    pub fn test_describe_schema_table() {
        let sql = "DESCRIBE TABLE test_schema.test";
        let stmts: Vec<Statement> =
            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default())
                .unwrap();
        assert_eq!(1, stmts.len());
        assert_matches!(&stmts[0], Statement::DescribeTable { .. });
        match &stmts[0] {
            Statement::DescribeTable(show) => {
                assert_eq!(format_raw_object_name(&show.name), "test_schema.test");
            }
            _ => {
                unreachable!();
            }
        }
    }

    #[test]
    pub fn test_describe_catalog_schema_table() {
        let sql = "DESCRIBE TABLE test_catalog.test_schema.test";
        let stmts: Vec<Statement> =
            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default())
                .unwrap();
        assert_eq!(1, stmts.len());
        assert_matches!(&stmts[0], Statement::DescribeTable { .. });
        match &stmts[0] {
            Statement::DescribeTable(show) => {
                assert_eq!(
                    format_raw_object_name(&show.name),
                    "test_catalog.test_schema.test"
                );
            }
            _ => {
                unreachable!();
            }
        }
    }

    #[test]
    pub fn test_describe_missing_table_name() {
        let sql = "DESCRIBE TABLE";
        assert!(ParserContext::create_with_dialect(
            sql,
            &GreptimeDbDialect {},
            ParseOptions::default()
        )
        .is_err());
    }

    #[test]
    fn test_display_describe_table() {
        let sql = r"describe table monitor;";
        let stmts =
            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default())
                .unwrap();
        assert_eq!(1, stmts.len());
        assert_matches!(&stmts[0], Statement::DescribeTable { .. });

        match &stmts[0] {
            Statement::DescribeTable(set) => {
                let new_sql = format!("\n{}", set);
                assert_eq!(
                    r#"
DESCRIBE TABLE monitor"#,
                    &new_sql
                );
            }
            _ => {
                unreachable!();
            }
        }
    }
}