store_api/storage/
consts.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
15//! Constants.
16
17use crate::storage::descriptors::ColumnId;
18
19// ---------- Reserved column ids ----------------------------------------------
20
21// The reserved column id is too large to be defined as enum value (denied by the
22// `clippy::enum_clike_unportable_variant` lint). So we add this enum as offset
23// in ReservedColumnId to get the final column id.
24enum ReservedColumnType {
25    Version = 0,
26    Sequence,
27    OpType,
28    Tsid,
29    TableId,
30}
31
32/// Column id reserved by the engine.
33///
34/// All reserved column id has MSB (Most Significant Bit) set to 1.
35///
36/// Reserved column includes version column and other internal columns.
37pub struct ReservedColumnId;
38
39impl ReservedColumnId {
40    // Set MSB to 1.
41    const BASE: ColumnId = 1 << (ColumnId::BITS - 1);
42
43    /// Column id for version column.
44    /// Version column is a special reserved column that is enabled by user and
45    /// visible to user.
46    pub const fn version() -> ColumnId {
47        Self::BASE | ReservedColumnType::Version as ColumnId
48    }
49
50    /// Id for `__sequence` column.
51    pub const fn sequence() -> ColumnId {
52        Self::BASE | ReservedColumnType::Sequence as ColumnId
53    }
54
55    /// Id for `__op_type` column.
56    pub const fn op_type() -> ColumnId {
57        Self::BASE | ReservedColumnType::OpType as ColumnId
58    }
59
60    /// Id for storing TSID column.
61    ///
62    /// Used by: metric engine
63    pub const fn tsid() -> ColumnId {
64        Self::BASE | ReservedColumnType::Tsid as ColumnId
65    }
66
67    /// Id for storing logical table id column.
68    ///
69    /// Used by: metric engine
70    pub const fn table_id() -> ColumnId {
71        Self::BASE | ReservedColumnType::TableId as ColumnId
72    }
73
74    /// Test if the column id is reserved.
75    pub fn is_reserved(column_id: ColumnId) -> bool {
76        column_id & Self::BASE != 0
77    }
78}
79
80// -----------------------------------------------------------------------------
81
82// ---------- Names reserved for internal columns and engine -------------------
83
84/// Name for reserved column: sequence
85pub const SEQUENCE_COLUMN_NAME: &str = "__sequence";
86
87/// Name for reserved column: op_type
88pub const OP_TYPE_COLUMN_NAME: &str = "__op_type";
89
90/// Name for reserved column: primary_key
91pub const PRIMARY_KEY_COLUMN_NAME: &str = "__primary_key";
92
93/// Internal Column Name
94static INTERNAL_COLUMN_VEC: [&str; 3] = [
95    SEQUENCE_COLUMN_NAME,
96    OP_TYPE_COLUMN_NAME,
97    PRIMARY_KEY_COLUMN_NAME,
98];
99
100pub fn is_internal_column(name: &str) -> bool {
101    INTERNAL_COLUMN_VEC.contains(&name)
102}
103
104// -----------------------------------------------------------------------------
105
106#[cfg(test)]
107mod tests {
108    use super::*;
109
110    #[test]
111    fn test_reserved_id() {
112        assert_eq!(0x80000000, ReservedColumnId::version());
113        assert_eq!(0x80000001, ReservedColumnId::sequence());
114        assert_eq!(0x80000002, ReservedColumnId::op_type());
115    }
116
117    #[test]
118    fn test_is_internal_column() {
119        // contain internal column names
120        assert!(is_internal_column(SEQUENCE_COLUMN_NAME));
121        assert!(is_internal_column(OP_TYPE_COLUMN_NAME));
122        assert!(is_internal_column(PRIMARY_KEY_COLUMN_NAME));
123
124        // don't contain internal column names
125        assert!(!is_internal_column("my__column"));
126        assert!(!is_internal_column("my__sequence"));
127        assert!(!is_internal_column("my__op_type"));
128        assert!(!is_internal_column("my__primary_key"));
129    }
130}
store_api/storage/consts.rs

store_api/storage/
consts.rs
