risingwave_meta/controller/
rename.rs

1// Copyright 2023 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_pb::expr::expr_node::{self, RexNode};
17use risingwave_pb::expr::{ExprNode, FunctionCall, UserDefinedFunction};
18use risingwave_pb::plan_common::PbColumnDesc;
19use risingwave_sqlparser::ast::{
20    Array, CdcTableInfo, CreateSink, CreateSinkStatement, CreateSourceStatement,
21    CreateSubscriptionStatement, Distinct, Expr, Function, FunctionArg, FunctionArgExpr,
22    FunctionArgList, Ident, ObjectName, Query, SelectItem, SetExpr, Statement, TableAlias,
23    TableFactor, TableWithJoins, Window,
24};
25use risingwave_sqlparser::parser::Parser;
26
27/// `alter_relation_rename` renames a relation to a new name in its `Create` statement, and returns
28/// the updated definition raw sql. Note that the `definition` must be a `Create` statement and the
29/// `new_name` must be a valid identifier, it should be validated before calling this function. To
30/// update all relations that depend on the renamed one, use `alter_relation_rename_refs`.
31pub fn alter_relation_rename(definition: &str, new_name: &str) -> String {
32    // This happens when we try to rename a table that's created by `CREATE TABLE AS`. Remove it
33    // when we support `SHOW CREATE TABLE` for `CREATE TABLE AS`.
34    if definition.is_empty() {
35        tracing::warn!("found empty definition when renaming relation, ignored.");
36        return definition.into();
37    }
38    let ast = Parser::parse_sql(definition).expect("failed to parse relation definition");
39    let mut stmt =
40        Itertools::exactly_one(ast.into_iter()).expect("should contains only one statement");
41
42    match &mut stmt {
43        Statement::CreateTable { name, .. }
44        | Statement::CreateView { name, .. }
45        | Statement::CreateIndex { name, .. }
46        | Statement::CreateSource {
47            stmt: CreateSourceStatement {
48                source_name: name, ..
49            },
50        }
51        | Statement::CreateSubscription {
52            stmt:
53                CreateSubscriptionStatement {
54                    subscription_name: name,
55                    ..
56                },
57        }
58        | Statement::CreateSink {
59            stmt: CreateSinkStatement {
60                sink_name: name, ..
61            },
62        } => replace_table_name(name, new_name),
63        _ => unreachable!(),
64    };
65
66    stmt.to_string()
67}
68
69/// `alter_relation_rename_refs` updates all references of renamed-relation in the definition of
70/// target relation's `Create` statement.
71pub fn alter_relation_rename_refs(definition: &str, from: &str, to: &str) -> String {
72    let ast = Parser::parse_sql(definition).expect("failed to parse relation definition");
73    let mut stmt =
74        Itertools::exactly_one(ast.into_iter()).expect("should contains only one statement");
75
76    match &mut stmt {
77        Statement::CreateTable {
78            query: Some(query), ..
79        }
80        | Statement::CreateView { query, .. }
81        | Statement::Query(query) // Used by view, actually we store a query as the definition of view.
82        | Statement::CreateSink {
83            stmt:
84            CreateSinkStatement {
85                sink_from: CreateSink::AsQuery(query),
86                into_table_name: None,
87                ..
88            },
89        } => {
90            QueryRewriter::rewrite_query(query, from, to);
91        }
92        Statement::CreateIndex { table_name, .. }
93        | Statement::CreateSink {
94            stmt:
95            CreateSinkStatement {
96                sink_from: CreateSink::From(table_name),
97                into_table_name: None,
98                ..
99            },
100        }| Statement::CreateSubscription {
101            stmt:
102            CreateSubscriptionStatement {
103                subscription_from: table_name,
104                ..
105            },
106        } | Statement::CreateTable {
107            cdc_table_info:
108            Some(CdcTableInfo {
109                source_name: table_name,
110                ..
111            }),
112            ..
113        } | Statement::CreateSource {
114            stmt: CreateSourceStatement {
115                cdc_table_info:
116                    Some(CdcTableInfo {
117                        source_name: table_name,
118                        ..
119                    }),
120                ..
121            },
122        } => replace_table_name(table_name, to),
123        Statement::CreateSink {
124            stmt: CreateSinkStatement {
125                sink_from,
126                into_table_name: Some(table_name),
127                ..
128            }
129        } => {
130            let idx = table_name.0.len() - 1;
131            if table_name.0[idx].real_value() == from {
132                table_name.0[idx] = Ident::from_real_value(to);
133            } else {
134                match sink_from {
135                    CreateSink::From(table_name) => replace_table_name(table_name, to),
136                    CreateSink::AsQuery(query) => QueryRewriter::rewrite_query(query, from, to),
137                }
138            }
139        }
140        _ => unreachable!(),
141    };
142    stmt.to_string()
143}
144
145/// Replace the last ident in the `table_name` with the given name, the object name is ensured to be
146/// non-empty. e.g. `schema.table` or `database.schema.table`.
147fn replace_table_name(table_name: &mut ObjectName, to: &str) {
148    let idx = table_name.0.len() - 1;
149    table_name.0[idx] = Ident::from_real_value(to);
150}
151
152/// `QueryRewriter` is a visitor that updates all references of relation named `from` to `to` in the
153/// given query, which is the part of create statement of `relation`.
154struct QueryRewriter<'a> {
155    from: &'a str,
156    to: &'a str,
157}
158
159impl QueryRewriter<'_> {
160    fn rewrite_query(query: &mut Query, from: &str, to: &str) {
161        let rewriter = QueryRewriter { from, to };
162        rewriter.visit_query(query)
163    }
164
165    /// Visit the query and update all references of relation named `from` to `to`.
166    fn visit_query(&self, query: &mut Query) {
167        if let Some(with) = &mut query.with {
168            for cte_table in &mut with.cte_tables {
169                match &mut cte_table.cte_inner {
170                    risingwave_sqlparser::ast::CteInner::Query(query) => self.visit_query(query),
171                    risingwave_sqlparser::ast::CteInner::ChangeLog(name) => {
172                        let idx = name.0.len() - 1;
173                        if name.0[idx].real_value() == self.from {
174                            replace_table_name(name, self.to);
175                        }
176                    }
177                }
178            }
179        }
180        self.visit_set_expr(&mut query.body);
181        for expr in &mut query.order_by {
182            self.visit_expr(&mut expr.expr);
183        }
184    }
185
186    /// Visit table factor and update all references of relation named `from` to `to`.
187    /// Rewrite idents(i.e. `schema.table`, `table`) that contains the old name in the
188    /// following pattern:
189    /// 1. `FROM a` to `FROM new_a AS a`
190    /// 2. `FROM a AS b` to `FROM new_a AS b`
191    ///
192    /// So that we DON'T have to:
193    /// 1. rewrite the select and expr part like `schema.table.column`, `table.column`,
194    ///    `alias.column` etc.
195    /// 2. handle the case that the old name is used as alias.
196    /// 3. handle the case that the new name is used as alias.
197    fn visit_table_factor(&self, table_factor: &mut TableFactor) {
198        match table_factor {
199            TableFactor::Table { name, alias, .. } => {
200                let idx = name.0.len() - 1;
201                if name.0[idx].real_value() == self.from {
202                    if alias.is_none() {
203                        *alias = Some(TableAlias {
204                            name: Ident::from_real_value(self.from),
205                            columns: vec![],
206                        });
207                    }
208                    name.0[idx] = Ident::from_real_value(self.to);
209                }
210            }
211            TableFactor::Derived { subquery, .. } => self.visit_query(subquery),
212            TableFactor::TableFunction { args, .. } => {
213                for arg in args {
214                    self.visit_function_arg(arg);
215                }
216            }
217            TableFactor::NestedJoin(table_with_joins) => {
218                self.visit_table_with_joins(table_with_joins);
219            }
220            TableFactor::MatchRecognize { table, .. } => {
221                // Only the input table can reference a relation: the binder rejects subqueries in
222                // both DEFINE and MEASURES (they have no representation in the executor's scalar
223                // expressions), so the remaining clauses contain no rename targets.
224                self.visit_table_factor(table);
225            }
226        }
227    }
228
229    /// Visit table with joins and update all references of relation named `from` to `to`.
230    fn visit_table_with_joins(&self, table_with_joins: &mut TableWithJoins) {
231        self.visit_table_factor(&mut table_with_joins.relation);
232        for join in &mut table_with_joins.joins {
233            self.visit_table_factor(&mut join.relation);
234        }
235    }
236
237    /// Visit query body expression and update all references.
238    fn visit_set_expr(&self, set_expr: &mut SetExpr) {
239        match set_expr {
240            SetExpr::Select(select) => {
241                if let Distinct::DistinctOn(exprs) = &mut select.distinct {
242                    for expr in exprs {
243                        self.visit_expr(expr);
244                    }
245                }
246                for select_item in &mut select.projection {
247                    self.visit_select_item(select_item);
248                }
249                for from_item in &mut select.from {
250                    self.visit_table_with_joins(from_item);
251                }
252                if let Some(where_clause) = &mut select.selection {
253                    self.visit_expr(where_clause);
254                }
255                for expr in &mut select.group_by {
256                    self.visit_expr(expr);
257                }
258                if let Some(having) = &mut select.having {
259                    self.visit_expr(having);
260                }
261                for named_window in &mut select.window {
262                    for expr in &mut named_window.window_spec.partition_by {
263                        self.visit_expr(expr);
264                    }
265                    for expr in &mut named_window.window_spec.order_by {
266                        self.visit_expr(&mut expr.expr);
267                    }
268                }
269            }
270            SetExpr::Query(query) => self.visit_query(query),
271            SetExpr::SetOperation { left, right, .. } => {
272                self.visit_set_expr(left);
273                self.visit_set_expr(right);
274            }
275            SetExpr::Values(_) => {}
276        }
277    }
278
279    /// Visit function arguments and update all references.
280    fn visit_function_arg(&self, function_arg: &mut FunctionArg) {
281        match function_arg {
282            FunctionArg::Unnamed(arg) | FunctionArg::Named { arg, .. } => match arg {
283                FunctionArgExpr::Expr(expr) | FunctionArgExpr::ExprQualifiedWildcard(expr, _) => {
284                    self.visit_expr(expr)
285                }
286                FunctionArgExpr::QualifiedWildcard(_, None) | FunctionArgExpr::Wildcard(None) => {}
287                FunctionArgExpr::QualifiedWildcard(_, Some(exprs))
288                | FunctionArgExpr::Wildcard(Some(exprs)) => {
289                    for expr in exprs {
290                        self.visit_expr(expr);
291                    }
292                }
293                FunctionArgExpr::SecretRef(_) => {}
294            },
295        }
296    }
297
298    fn visit_function_arg_list(&self, arg_list: &mut FunctionArgList) {
299        for arg in &mut arg_list.args {
300            self.visit_function_arg(arg);
301        }
302        for expr in &mut arg_list.order_by {
303            self.visit_expr(&mut expr.expr)
304        }
305    }
306
307    /// Visit function and update all references.
308    fn visit_function(&self, function: &mut Function) {
309        self.visit_function_arg_list(&mut function.arg_list);
310        if let Some(over) = &mut function.over {
311            match over {
312                Window::Spec(window) => {
313                    for expr in &mut window.partition_by {
314                        self.visit_expr(expr);
315                    }
316                    for expr in &mut window.order_by {
317                        self.visit_expr(&mut expr.expr);
318                    }
319                }
320                Window::Name(_) => {
321                    // Named window references don't contain expressions to rewrite
322                }
323            }
324        }
325    }
326
327    /// Visit expression and update all references.
328    fn visit_expr(&self, expr: &mut Expr) {
329        match expr {
330            Expr::FieldIdentifier(expr, ..)
331            | Expr::IsNull(expr)
332            | Expr::IsNotNull(expr)
333            | Expr::IsTrue(expr)
334            | Expr::IsNotTrue(expr)
335            | Expr::IsFalse(expr)
336            | Expr::IsNotFalse(expr)
337            | Expr::IsUnknown(expr)
338            | Expr::IsNotUnknown(expr)
339            | Expr::IsJson { expr, .. }
340            | Expr::InList { expr, .. }
341            | Expr::SomeOp(expr)
342            | Expr::AllOp(expr)
343            | Expr::UnaryOp { expr, .. }
344            | Expr::Cast { expr, .. }
345            | Expr::TryCast { expr, .. }
346            | Expr::AtTimeZone {
347                timestamp: expr, ..
348            }
349            | Expr::Extract { expr, .. }
350            | Expr::Substring { expr, .. }
351            | Expr::Overlay { expr, .. }
352            | Expr::Trim { expr, .. }
353            | Expr::Nested(expr)
354            | Expr::Index { obj: expr, .. }
355            | Expr::ArrayRangeIndex { obj: expr, .. } => self.visit_expr(expr),
356
357            Expr::Position { substring, string } => {
358                self.visit_expr(substring);
359                self.visit_expr(string);
360            }
361
362            Expr::InSubquery { expr, subquery, .. } => {
363                self.visit_expr(expr);
364                self.visit_query(subquery);
365            }
366            Expr::Between {
367                expr, low, high, ..
368            } => {
369                self.visit_expr(expr);
370                self.visit_expr(low);
371                self.visit_expr(high);
372            }
373            Expr::Like {
374                expr, pattern: pat, ..
375            } => {
376                self.visit_expr(expr);
377                self.visit_expr(pat);
378            }
379            Expr::ILike {
380                expr, pattern: pat, ..
381            } => {
382                self.visit_expr(expr);
383                self.visit_expr(pat);
384            }
385            Expr::SimilarTo {
386                expr, pattern: pat, ..
387            } => {
388                self.visit_expr(expr);
389                self.visit_expr(pat);
390            }
391
392            Expr::IsDistinctFrom(expr1, expr2)
393            | Expr::IsNotDistinctFrom(expr1, expr2)
394            | Expr::BinaryOp {
395                left: expr1,
396                right: expr2,
397                ..
398            } => {
399                self.visit_expr(expr1);
400                self.visit_expr(expr2);
401            }
402            Expr::Function(function) => self.visit_function(function),
403            Expr::Exists(query) | Expr::Subquery(query) | Expr::ArraySubquery(query) => {
404                self.visit_query(query)
405            }
406
407            Expr::GroupingSets(exprs_vec) | Expr::Cube(exprs_vec) | Expr::Rollup(exprs_vec) => {
408                for exprs in exprs_vec {
409                    for expr in exprs {
410                        self.visit_expr(expr);
411                    }
412                }
413            }
414
415            Expr::Row(exprs) | Expr::Array(Array { elem: exprs, .. }) => {
416                for expr in exprs {
417                    self.visit_expr(expr);
418                }
419            }
420            Expr::Map { entries } => {
421                for (key, value) in entries {
422                    self.visit_expr(key);
423                    self.visit_expr(value);
424                }
425            }
426
427            Expr::LambdaFunction { body, args: _ } => self.visit_expr(body),
428
429            // No need to visit.
430            Expr::Identifier(_)
431            | Expr::CompoundIdentifier(_)
432            | Expr::Collate { .. }
433            | Expr::Value(_)
434            | Expr::Parameter { .. }
435            | Expr::TypedString { .. }
436            | Expr::Case { .. } => {}
437        }
438    }
439
440    /// Visit select item and update all references.
441    fn visit_select_item(&self, select_item: &mut SelectItem) {
442        match select_item {
443            SelectItem::UnnamedExpr(expr)
444            | SelectItem::ExprQualifiedWildcard(expr, _)
445            | SelectItem::ExprWithAlias { expr, .. } => self.visit_expr(expr),
446            SelectItem::QualifiedWildcard(_, None) | SelectItem::Wildcard(None) => {}
447            SelectItem::QualifiedWildcard(_, Some(exprs)) | SelectItem::Wildcard(Some(exprs)) => {
448                for expr in exprs {
449                    self.visit_expr(expr);
450                }
451            }
452        }
453    }
454}
455
456/// Rewrite the expression in index item after there's a schema change on the primary table.
457// TODO: move this out of `rename.rs`, this has nothing to do with renaming.
458pub struct IndexItemRewriter {
459    pub original_columns: Vec<PbColumnDesc>,
460    pub new_columns: Vec<PbColumnDesc>,
461}
462
463impl IndexItemRewriter {
464    pub fn rewrite_expr(&self, expr: &mut ExprNode) {
465        let rex_node = expr.rex_node.as_mut().unwrap();
466        match rex_node {
467            RexNode::InputRef(idx) => {
468                let old_idx = *idx as usize;
469                let original_column = &self.original_columns[old_idx];
470                let (new_idx, new_column) = self
471                    .new_columns
472                    .iter()
473                    .find_position(|c| c.column_id == original_column.column_id)
474                    .expect("should already checked index referencing column still exists");
475                *idx = new_idx as u32;
476
477                // If there's a type change, we need to wrap it with an internal `CompositeCast` to
478                // maintain the correct return type. It cannot execute and will be eliminated in
479                // the frontend when rebuilding the index items.
480                if new_column.column_type != original_column.column_type {
481                    let old_type = original_column.column_type.clone().unwrap();
482                    let new_type = new_column.column_type.clone().unwrap();
483
484                    assert_eq!(&old_type, expr.return_type.as_ref().unwrap());
485                    expr.return_type = Some(new_type); // update return type of `InputRef`
486
487                    let new_expr_node = ExprNode {
488                        function_type: expr_node::Type::CompositeCast as _,
489                        return_type: Some(old_type),
490                        rex_node: RexNode::FuncCall(FunctionCall {
491                            children: vec![expr.clone()],
492                        })
493                        .into(),
494                    };
495
496                    *expr = new_expr_node;
497                }
498            }
499            RexNode::Constant(_) => {}
500            RexNode::Udf(udf) => self.rewrite_udf(udf),
501            RexNode::FuncCall(function_call) => self.rewrite_function_call(function_call),
502            RexNode::Now(_) | RexNode::SecretRef(_) => {}
503        }
504    }
505
506    fn rewrite_udf(&self, udf: &mut UserDefinedFunction) {
507        udf.children
508            .iter_mut()
509            .for_each(|expr| self.rewrite_expr(expr));
510    }
511
512    fn rewrite_function_call(&self, function_call: &mut FunctionCall) {
513        function_call
514            .children
515            .iter_mut()
516            .for_each(|expr| self.rewrite_expr(expr));
517    }
518}
519
520#[cfg(test)]
521mod tests {
522    use super::*;
523
524    #[test]
525    fn test_alter_table_rename() {
526        let definition = "CREATE TABLE foo (a int, b int)";
527        let new_name = "bar";
528        let expected = "CREATE TABLE bar (a INT, b INT)";
529        let actual = alter_relation_rename(definition, new_name);
530        assert_eq!(expected, actual);
531    }
532
533    #[test]
534    fn test_rename_index_refs() {
535        let definition = "CREATE INDEX idx1 ON foo(v1 DESC, v2)";
536        let from = "foo";
537        let to = "bar";
538        let expected = "CREATE INDEX idx1 ON bar(v1 DESC, v2)";
539        let actual = alter_relation_rename_refs(definition, from, to);
540        assert_eq!(expected, actual);
541    }
542
543    #[test]
544    fn test_rename_sink_refs() {
545        let definition =
546            "CREATE SINK sink_t FROM foo WITH (connector = 'kafka', format = 'append_only')";
547        let from = "foo";
548        let to = "bar";
549        let expected =
550            "CREATE SINK sink_t FROM bar WITH (connector = 'kafka', format = 'append_only')";
551        let actual = alter_relation_rename_refs(definition, from, to);
552        assert_eq!(expected, actual);
553    }
554
555    #[test]
556    fn test_rename_with_alias_refs() {
557        let definition =
558            "CREATE MATERIALIZED VIEW mv1 AS SELECT foo.v1 AS m1v, foo.v2 AS m2v FROM foo";
559        let from = "foo";
560        let to = "bar";
561        let expected =
562            "CREATE MATERIALIZED VIEW mv1 AS SELECT foo.v1 AS m1v, foo.v2 AS m2v FROM bar AS foo";
563        let actual = alter_relation_rename_refs(definition, from, to);
564        assert_eq!(expected, actual);
565
566        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";
567        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";
568        let actual = alter_relation_rename_refs(definition, from, to);
569        assert_eq!(expected, actual);
570
571        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";
572        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";
573        let actual = alter_relation_rename_refs(definition, from, to);
574        assert_eq!(expected, actual);
575    }
576
577    #[test]
578    fn test_rename_with_complex_funcs() {
579        let definition = "CREATE MATERIALIZED VIEW mv1 AS SELECT \
580                            agg1(\
581                              foo.v1, func2(foo.v2) \
582                              ORDER BY \
583                              (SELECT foo.v3 FROM foo), \
584                              (SELECT first_value(foo.v4) OVER (PARTITION BY (SELECT foo.v5 FROM foo) ORDER BY (SELECT foo.v6 FROM foo)) FROM foo)\
585                            ) \
586                          FROM foo";
587        let from = "foo";
588        let to = "bar";
589        let expected = "CREATE MATERIALIZED VIEW mv1 AS SELECT \
590                          agg1(\
591                            foo.v1, func2(foo.v2) \
592                            ORDER BY \
593                            (SELECT foo.v3 FROM bar AS foo), \
594                            (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)\
595                          ) \
596                        FROM bar AS foo";
597        let actual = alter_relation_rename_refs(definition, from, to);
598        assert_eq!(expected, actual);
599    }
600}
risingwave_meta/controller/rename.rs

risingwave_meta/controller/
rename.rs
