risingwave_frontend/handler/
drop_schema.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 pgwire::pg_response::{PgResponse, StatementType};
16use risingwave_common::catalog::is_system_schema;
17use risingwave_sqlparser::ast::{DropMode, ObjectName};
18
19use super::RwPgResponse;
20use crate::binder::Binder;
21use crate::error::{ErrorCode, Result};
22use crate::handler::HandlerArgs;
23
24pub async fn handle_drop_schema(
25    handler_args: HandlerArgs,
26    schema_name: ObjectName,
27    if_exist: bool,
28    mode: Option<DropMode>,
29) -> Result<RwPgResponse> {
30    let session = handler_args.session;
31    let catalog_reader = session.env().catalog_reader();
32    let schema_name = Binder::resolve_schema_name(schema_name)?;
33
34    if is_system_schema(&schema_name) {
35        return Err(ErrorCode::ProtocolError(format!(
36            "cannot drop schema {} because it is required by the database system",
37            schema_name
38        ))
39        .into());
40    }
41
42    let schema = {
43        let reader = catalog_reader.read_guard();
44        match reader.get_schema_by_name(&session.database(), &schema_name) {
45            Ok(schema) => schema.clone(),
46            Err(err) => {
47                // If `if_exist` is true, not return error.
48                return if if_exist {
49                    Ok(PgResponse::builder(StatementType::DROP_SCHEMA)
50                        .notice(format!(
51                            "schema \"{}\" does not exist, skipping",
52                            schema_name
53                        ))
54                        .into())
55                } else {
56                    Err(err.into())
57                };
58            }
59        }
60    };
61
62    // Note: we don't check if the schema is empty here when drop mode is cascade.
63    // The check is done in meta `ensure_schema_empty`.
64    let cascade = matches!(mode, Some(DropMode::Cascade));
65
66    session.check_privilege_for_drop_alter_db_schema(&schema)?;
67
68    let catalog_writer = session.catalog_writer()?;
69    catalog_writer.drop_schema(schema.id(), cascade).await?;
70    Ok(PgResponse::empty_result(StatementType::DROP_SCHEMA))
71}
risingwave_frontend/handler/drop_schema.rs

risingwave_frontend/handler/
drop_schema.rs
