risingwave_frontend/catalog/system_catalog/rw_catalog/
rw_description.rs

1// Copyright 2025 RisingWave Labs
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::iter;
16
17use risingwave_common::catalog::RW_CATALOG_SCHEMA_NAME;
18use risingwave_common::types::Fields;
19use risingwave_frontend_macro::system_catalog;
20
21use crate::catalog::system_catalog::SysCatalogReaderImpl;
22use crate::error::Result;
23
24#[derive(Fields)]
25#[primary_key(objoid, classoid, objsubid)]
26struct RwDescription {
27    // table_id, view_id, function_id, etc.
28    objoid: i32,
29    // rw_tables, rw_views, rw_functions, etc.
30    classoid: i32,
31    // If `objoid` is `table_id`, then non-null `objsubid` is column number.
32    objsubid: Option<i32>,
33    description: Option<String>,
34}
35
36#[system_catalog(table, "rw_catalog.rw_description")]
37fn read(reader: &SysCatalogReaderImpl) -> Result<Vec<RwDescription>> {
38    let build_row =
39        |table_id, catalog_id, index: Option<i32>, description: Option<Box<str>>| RwDescription {
40            objoid: table_id,
41            classoid: catalog_id,
42            objsubid: index,
43            description: description.map(|s| s.into()),
44        };
45
46    let catalog_reader = reader.catalog_reader.read_guard();
47    let rw_catalog =
48        catalog_reader.get_schema_by_name(&reader.auth_context.database, RW_CATALOG_SCHEMA_NAME)?;
49    let schemas = catalog_reader
50        .iter_schemas(&reader.auth_context.database)?
51        .filter(|schema| schema.id() != rw_catalog.id());
52
53    let rw_tables_id: i32 = rw_catalog
54        .get_system_table_by_name("rw_tables")
55        .map(|st| st.id.table_id)
56        .unwrap_or_default() as _;
57
58    Ok(schemas
59        .flat_map(|schema| {
60            schema.iter_user_table().flat_map(|table| {
61                iter::once(build_row(
62                    table.id.table_id as _,
63                    rw_tables_id,
64                    None,
65                    table.description.as_deref().map(Into::into),
66                ))
67                .chain(table.columns.iter().map(|col| {
68                    build_row(
69                        table.id.table_id as _,
70                        rw_tables_id,
71                        Some(col.column_id().get_id() as _),
72                        col.column_desc.description.as_deref().map(Into::into),
73                    )
74                }))
75            })
76        })
77        .collect())
78}
risingwave_frontend/catalog/system_catalog/rw_catalog/rw_description.rs

risingwave_frontend/catalog/system_catalog/rw_catalog/
rw_description.rs
