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

risingwave_meta/controller/
rename.rs
