risingwave_meta/controller/
rename.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 itertools::Itertools;
16use risingwave_common::util::column_index_mapping::ColIndexMapping;
17use risingwave_pb::expr::expr_node::RexNode;
18use risingwave_pb::expr::{ExprNode, FunctionCall, UserDefinedFunction};
19use risingwave_sqlparser::ast::{
20    Array, CreateSink, CreateSinkStatement, CreateSourceStatement, CreateSubscriptionStatement,
21    Distinct, Expr, Function, FunctionArg, FunctionArgExpr, FunctionArgList, Ident, ObjectName,
22    Query, SelectItem, SetExpr, Statement, TableAlias, TableFactor, TableWithJoins,
23};
24use risingwave_sqlparser::parser::Parser;
25
26/// `alter_relation_rename` renames a relation to a new name in its `Create` statement, and returns
27/// the updated definition raw sql. Note that the `definition` must be a `Create` statement and the
28/// `new_name` must be a valid identifier, it should be validated before calling this function. To
29/// update all relations that depend on the renamed one, use `alter_relation_rename_refs`.
30pub fn alter_relation_rename(definition: &str, new_name: &str) -> String {
31    // This happens when we try to rename a table that's created by `CREATE TABLE AS`. Remove it
32    // when we support `SHOW CREATE TABLE` for `CREATE TABLE AS`.
33    if definition.is_empty() {
34        tracing::warn!("found empty definition when renaming relation, ignored.");
35        return definition.into();
36    }
37    let ast = Parser::parse_sql(definition).expect("failed to parse relation definition");
38    let mut stmt = ast
39        .into_iter()
40        .exactly_one()
41        .expect("should contains only one statement");
42
43    match &mut stmt {
44        Statement::CreateTable { name, .. }
45        | Statement::CreateView { name, .. }
46        | Statement::CreateIndex { name, .. }
47        | Statement::CreateSource {
48            stmt: CreateSourceStatement {
49                source_name: name, ..
50            },
51        }
52        | Statement::CreateSubscription {
53            stmt:
54                CreateSubscriptionStatement {
55                    subscription_name: name,
56                    ..
57                },
58        }
59        | Statement::CreateSink {
60            stmt: CreateSinkStatement {
61                sink_name: name, ..
62            },
63        } => replace_table_name(name, new_name),
64        _ => unreachable!(),
65    };
66
67    stmt.to_string()
68}
69
70/// `alter_relation_rename_refs` updates all references of renamed-relation in the definition of
71/// target relation's `Create` statement.
72pub fn alter_relation_rename_refs(definition: &str, from: &str, to: &str) -> String {
73    let ast = Parser::parse_sql(definition).expect("failed to parse relation definition");
74    let mut stmt = ast
75        .into_iter()
76        .exactly_one()
77        .expect("should contains only one statement");
78
79    match &mut stmt {
80        Statement::CreateTable {
81            query: Some(query), ..
82        }
83        | Statement::CreateView { query, .. }
84        | Statement::Query(query) // Used by view, actually we store a query as the definition of view.
85        | Statement::CreateSink {
86            stmt:
87            CreateSinkStatement {
88                sink_from: CreateSink::AsQuery(query),
89                into_table_name: None,
90                ..
91            },
92        } => {
93            QueryRewriter::rewrite_query(query, from, to);
94        }
95        Statement::CreateIndex { table_name, .. }
96        | Statement::CreateSink {
97            stmt:
98            CreateSinkStatement {
99                sink_from: CreateSink::From(table_name),
100                into_table_name: None,
101                ..
102            },
103        }| Statement::CreateSubscription {
104            stmt:
105            CreateSubscriptionStatement {
106                subscription_from: table_name,
107                ..
108            },
109        } => replace_table_name(table_name, to),
110        Statement::CreateSink {
111            stmt: CreateSinkStatement {
112                sink_from,
113                into_table_name: Some(table_name),
114                ..
115            }
116        } => {
117            let idx = table_name.0.len() - 1;
118            if table_name.0[idx].real_value() == from {
119                table_name.0[idx] = Ident::new_unchecked(to);
120            } else {
121                match sink_from {
122                    CreateSink::From(table_name) => replace_table_name(table_name, to),
123                    CreateSink::AsQuery(query) => QueryRewriter::rewrite_query(query, from, to),
124                }
125            }
126        }
127        _ => unreachable!(),
128    };
129    stmt.to_string()
130}
131
132/// Replace the last ident in the `table_name` with the given name, the object name is ensured to be
133/// non-empty. e.g. `schema.table` or `database.schema.table`.
134fn replace_table_name(table_name: &mut ObjectName, to: &str) {
135    let idx = table_name.0.len() - 1;
136    table_name.0[idx] = Ident::new_unchecked(to);
137}
138
139/// `QueryRewriter` is a visitor that updates all references of relation named `from` to `to` in the
140/// given query, which is the part of create statement of `relation`.
141struct QueryRewriter<'a> {
142    from: &'a str,
143    to: &'a str,
144}
145
146impl QueryRewriter<'_> {
147    fn rewrite_query(query: &mut Query, from: &str, to: &str) {
148        let rewriter = QueryRewriter { from, to };
149        rewriter.visit_query(query)
150    }
151
152    /// Visit the query and update all references of relation named `from` to `to`.
153    fn visit_query(&self, query: &mut Query) {
154        if let Some(with) = &mut query.with {
155            for cte_table in &mut with.cte_tables {
156                match &mut cte_table.cte_inner {
157                    risingwave_sqlparser::ast::CteInner::Query(query) => self.visit_query(query),
158                    risingwave_sqlparser::ast::CteInner::ChangeLog(name) => {
159                        let idx = name.0.len() - 1;
160                        if name.0[idx].real_value() == self.from {
161                            name.0[idx] = Ident::with_quote_unchecked('"', self.to);
162                        }
163                    }
164                }
165            }
166        }
167        self.visit_set_expr(&mut query.body);
168        for expr in &mut query.order_by {
169            self.visit_expr(&mut expr.expr);
170        }
171    }
172
173    /// Visit table factor and update all references of relation named `from` to `to`.
174    /// Rewrite idents(i.e. `schema.table`, `table`) that contains the old name in the
175    /// following pattern:
176    /// 1. `FROM a` to `FROM new_a AS a`
177    /// 2. `FROM a AS b` to `FROM new_a AS b`
178    ///
179    /// So that we DON'T have to:
180    /// 1. rewrite the select and expr part like `schema.table.column`, `table.column`,
181    ///    `alias.column` etc.
182    /// 2. handle the case that the old name is used as alias.
183    /// 3. handle the case that the new name is used as alias.
184    fn visit_table_factor(&self, table_factor: &mut TableFactor) {
185        match table_factor {
186            TableFactor::Table { name, alias, .. } => {
187                let idx = name.0.len() - 1;
188                if name.0[idx].real_value() == self.from {
189                    if alias.is_none() {
190                        *alias = Some(TableAlias {
191                            name: Ident::new_unchecked(self.from),
192                            columns: vec![],
193                        });
194                    }
195                    name.0[idx] = Ident::new_unchecked(self.to);
196                }
197            }
198            TableFactor::Derived { subquery, .. } => self.visit_query(subquery),
199            TableFactor::TableFunction { args, .. } => {
200                for arg in args {
201                    self.visit_function_arg(arg);
202                }
203            }
204            TableFactor::NestedJoin(table_with_joins) => {
205                self.visit_table_with_joins(table_with_joins);
206            }
207        }
208    }
209
210    /// Visit table with joins and update all references of relation named `from` to `to`.
211    fn visit_table_with_joins(&self, table_with_joins: &mut TableWithJoins) {
212        self.visit_table_factor(&mut table_with_joins.relation);
213        for join in &mut table_with_joins.joins {
214            self.visit_table_factor(&mut join.relation);
215        }
216    }
217
218    /// Visit query body expression and update all references.
219    fn visit_set_expr(&self, set_expr: &mut SetExpr) {
220        match set_expr {
221            SetExpr::Select(select) => {
222                if let Distinct::DistinctOn(exprs) = &mut select.distinct {
223                    for expr in exprs {
224                        self.visit_expr(expr);
225                    }
226                }
227                for select_item in &mut select.projection {
228                    self.visit_select_item(select_item);
229                }
230                for from_item in &mut select.from {
231                    self.visit_table_with_joins(from_item);
232                }
233                if let Some(where_clause) = &mut select.selection {
234                    self.visit_expr(where_clause);
235                }
236                for expr in &mut select.group_by {
237                    self.visit_expr(expr);
238                }
239                if let Some(having) = &mut select.having {
240                    self.visit_expr(having);
241                }
242            }
243            SetExpr::Query(query) => self.visit_query(query),
244            SetExpr::SetOperation { left, right, .. } => {
245                self.visit_set_expr(left);
246                self.visit_set_expr(right);
247            }
248            SetExpr::Values(_) => {}
249        }
250    }
251
252    /// Visit function arguments and update all references.
253    fn visit_function_arg(&self, function_arg: &mut FunctionArg) {
254        match function_arg {
255            FunctionArg::Unnamed(arg) | FunctionArg::Named { arg, .. } => match arg {
256                FunctionArgExpr::Expr(expr) | FunctionArgExpr::ExprQualifiedWildcard(expr, _) => {
257                    self.visit_expr(expr)
258                }
259                FunctionArgExpr::QualifiedWildcard(_, None) | FunctionArgExpr::Wildcard(None) => {}
260                FunctionArgExpr::QualifiedWildcard(_, Some(exprs))
261                | FunctionArgExpr::Wildcard(Some(exprs)) => {
262                    for expr in exprs {
263                        self.visit_expr(expr);
264                    }
265                }
266            },
267        }
268    }
269
270    fn visit_function_arg_list(&self, arg_list: &mut FunctionArgList) {
271        for arg in &mut arg_list.args {
272            self.visit_function_arg(arg);
273        }
274        for expr in &mut arg_list.order_by {
275            self.visit_expr(&mut expr.expr)
276        }
277    }
278
279    /// Visit function and update all references.
280    fn visit_function(&self, function: &mut Function) {
281        self.visit_function_arg_list(&mut function.arg_list);
282        if let Some(over) = &mut function.over {
283            for expr in &mut over.partition_by {
284                self.visit_expr(expr);
285            }
286            for expr in &mut over.order_by {
287                self.visit_expr(&mut expr.expr);
288            }
289        }
290    }
291
292    /// Visit expression and update all references.
293    fn visit_expr(&self, expr: &mut Expr) {
294        match expr {
295            Expr::FieldIdentifier(expr, ..)
296            | Expr::IsNull(expr)
297            | Expr::IsNotNull(expr)
298            | Expr::IsTrue(expr)
299            | Expr::IsNotTrue(expr)
300            | Expr::IsFalse(expr)
301            | Expr::IsNotFalse(expr)
302            | Expr::IsUnknown(expr)
303            | Expr::IsNotUnknown(expr)
304            | Expr::IsJson { expr, .. }
305            | Expr::InList { expr, .. }
306            | Expr::SomeOp(expr)
307            | Expr::AllOp(expr)
308            | Expr::UnaryOp { expr, .. }
309            | Expr::Cast { expr, .. }
310            | Expr::TryCast { expr, .. }
311            | Expr::AtTimeZone {
312                timestamp: expr, ..
313            }
314            | Expr::Extract { expr, .. }
315            | Expr::Substring { expr, .. }
316            | Expr::Overlay { expr, .. }
317            | Expr::Trim { expr, .. }
318            | Expr::Nested(expr)
319            | Expr::Index { obj: expr, .. }
320            | Expr::ArrayRangeIndex { obj: expr, .. } => self.visit_expr(expr),
321
322            Expr::Position { substring, string } => {
323                self.visit_expr(substring);
324                self.visit_expr(string);
325            }
326
327            Expr::InSubquery { expr, subquery, .. } => {
328                self.visit_expr(expr);
329                self.visit_query(subquery);
330            }
331            Expr::Between {
332                expr, low, high, ..
333            } => {
334                self.visit_expr(expr);
335                self.visit_expr(low);
336                self.visit_expr(high);
337            }
338            Expr::Like {
339                expr, pattern: pat, ..
340            } => {
341                self.visit_expr(expr);
342                self.visit_expr(pat);
343            }
344            Expr::ILike {
345                expr, pattern: pat, ..
346            } => {
347                self.visit_expr(expr);
348                self.visit_expr(pat);
349            }
350            Expr::SimilarTo {
351                expr, pattern: pat, ..
352            } => {
353                self.visit_expr(expr);
354                self.visit_expr(pat);
355            }
356
357            Expr::IsDistinctFrom(expr1, expr2)
358            | Expr::IsNotDistinctFrom(expr1, expr2)
359            | Expr::BinaryOp {
360                left: expr1,
361                right: expr2,
362                ..
363            } => {
364                self.visit_expr(expr1);
365                self.visit_expr(expr2);
366            }
367            Expr::Function(function) => self.visit_function(function),
368            Expr::Exists(query) | Expr::Subquery(query) | Expr::ArraySubquery(query) => {
369                self.visit_query(query)
370            }
371
372            Expr::GroupingSets(exprs_vec) | Expr::Cube(exprs_vec) | Expr::Rollup(exprs_vec) => {
373                for exprs in exprs_vec {
374                    for expr in exprs {
375                        self.visit_expr(expr);
376                    }
377                }
378            }
379
380            Expr::Row(exprs) | Expr::Array(Array { elem: exprs, .. }) => {
381                for expr in exprs {
382                    self.visit_expr(expr);
383                }
384            }
385            Expr::Map { entries } => {
386                for (key, value) in entries {
387                    self.visit_expr(key);
388                    self.visit_expr(value);
389                }
390            }
391
392            Expr::LambdaFunction { body, args: _ } => self.visit_expr(body),
393
394            // No need to visit.
395            Expr::Identifier(_)
396            | Expr::CompoundIdentifier(_)
397            | Expr::Collate { .. }
398            | Expr::Value(_)
399            | Expr::Parameter { .. }
400            | Expr::TypedString { .. }
401            | Expr::Case { .. } => {}
402        }
403    }
404
405    /// Visit select item and update all references.
406    fn visit_select_item(&self, select_item: &mut SelectItem) {
407        match select_item {
408            SelectItem::UnnamedExpr(expr)
409            | SelectItem::ExprQualifiedWildcard(expr, _)
410            | SelectItem::ExprWithAlias { expr, .. } => self.visit_expr(expr),
411            SelectItem::QualifiedWildcard(_, None) | SelectItem::Wildcard(None) => {}
412            SelectItem::QualifiedWildcard(_, Some(exprs)) | SelectItem::Wildcard(Some(exprs)) => {
413                for expr in exprs {
414                    self.visit_expr(expr);
415                }
416            }
417        }
418    }
419}
420
421pub struct ReplaceTableExprRewriter {
422    pub table_col_index_mapping: ColIndexMapping,
423}
424
425impl ReplaceTableExprRewriter {
426    pub fn rewrite_expr(&self, expr: &mut ExprNode) {
427        let rex_node = expr.rex_node.as_mut().unwrap();
428        match rex_node {
429            RexNode::InputRef(input_col_idx) => {
430                *input_col_idx = self.table_col_index_mapping.map(*input_col_idx as usize) as u32
431            }
432            RexNode::Constant(_) => {}
433            RexNode::Udf(udf) => self.rewrite_udf(udf),
434            RexNode::FuncCall(function_call) => self.rewrite_function_call(function_call),
435            RexNode::Now(_) => {}
436        }
437    }
438
439    fn rewrite_udf(&self, udf: &mut UserDefinedFunction) {
440        udf.children
441            .iter_mut()
442            .for_each(|expr| self.rewrite_expr(expr));
443    }
444
445    fn rewrite_function_call(&self, function_call: &mut FunctionCall) {
446        function_call
447            .children
448            .iter_mut()
449            .for_each(|expr| self.rewrite_expr(expr));
450    }
451}
452
453#[cfg(test)]
454mod tests {
455    use super::*;
456
457    #[test]
458    fn test_alter_table_rename() {
459        let definition = "CREATE TABLE foo (a int, b int)";
460        let new_name = "bar";
461        let expected = "CREATE TABLE bar (a INT, b INT)";
462        let actual = alter_relation_rename(definition, new_name);
463        assert_eq!(expected, actual);
464    }
465
466    #[test]
467    fn test_rename_index_refs() {
468        let definition = "CREATE INDEX idx1 ON foo(v1 DESC, v2)";
469        let from = "foo";
470        let to = "bar";
471        let expected = "CREATE INDEX idx1 ON bar(v1 DESC, v2)";
472        let actual = alter_relation_rename_refs(definition, from, to);
473        assert_eq!(expected, actual);
474    }
475
476    #[test]
477    fn test_rename_sink_refs() {
478        let definition =
479            "CREATE SINK sink_t FROM foo WITH (connector = 'kafka', format = 'append_only')";
480        let from = "foo";
481        let to = "bar";
482        let expected =
483            "CREATE SINK sink_t FROM bar WITH (connector = 'kafka', format = 'append_only')";
484        let actual = alter_relation_rename_refs(definition, from, to);
485        assert_eq!(expected, actual);
486    }
487
488    #[test]
489    fn test_rename_with_alias_refs() {
490        let definition =
491            "CREATE MATERIALIZED VIEW mv1 AS SELECT foo.v1 AS m1v, foo.v2 AS m2v FROM foo";
492        let from = "foo";
493        let to = "bar";
494        let expected =
495            "CREATE MATERIALIZED VIEW mv1 AS SELECT foo.v1 AS m1v, foo.v2 AS m2v FROM bar AS foo";
496        let actual = alter_relation_rename_refs(definition, from, to);
497        assert_eq!(expected, actual);
498
499        let definition = "CREATE MATERIALIZED VIEW mv1 AS SELECT foo.v1 AS m1v, (foo.v2).v3 AS m2v FROM foo WHERE foo.v1 = 1 AND (foo.v2).v3 IS TRUE";
500        let expected = "CREATE MATERIALIZED VIEW mv1 AS SELECT foo.v1 AS m1v, (foo.v2).v3 AS m2v FROM bar AS foo WHERE foo.v1 = 1 AND (foo.v2).v3 IS TRUE";
501        let actual = alter_relation_rename_refs(definition, from, to);
502        assert_eq!(expected, actual);
503
504        let definition = "CREATE MATERIALIZED VIEW mv1 AS SELECT bar.v1 AS m1v, (bar.v2).v3 AS m2v FROM foo AS bar WHERE bar.v1 = 1";
505        let expected = "CREATE MATERIALIZED VIEW mv1 AS SELECT bar.v1 AS m1v, (bar.v2).v3 AS m2v FROM bar AS bar WHERE bar.v1 = 1";
506        let actual = alter_relation_rename_refs(definition, from, to);
507        assert_eq!(expected, actual);
508    }
509
510    #[test]
511    fn test_rename_with_complex_funcs() {
512        let definition = "CREATE MATERIALIZED VIEW mv1 AS SELECT \
513                            agg1(\
514                              foo.v1, func2(foo.v2) \
515                              ORDER BY \
516                              (SELECT foo.v3 FROM foo), \
517                              (SELECT first_value(foo.v4) OVER (PARTITION BY (SELECT foo.v5 FROM foo) ORDER BY (SELECT foo.v6 FROM foo)) FROM foo)\
518                            ) \
519                          FROM foo";
520        let from = "foo";
521        let to = "bar";
522        let expected = "CREATE MATERIALIZED VIEW mv1 AS SELECT \
523                          agg1(\
524                            foo.v1, func2(foo.v2) \
525                            ORDER BY \
526                            (SELECT foo.v3 FROM bar AS foo), \
527                            (SELECT first_value(foo.v4) OVER (PARTITION BY (SELECT foo.v5 FROM bar AS foo) ORDER BY (SELECT foo.v6 FROM bar AS foo)) FROM bar AS foo)\
528                          ) \
529                        FROM bar AS foo";
530        let actual = alter_relation_rename_refs(definition, from, to);
531        assert_eq!(expected, actual);
532    }
533}
risingwave_meta/controller/rename.rs

risingwave_meta/controller/
rename.rs
