*: add sys schema, sys.SCHEMA_UNUSED_INDEXES view and sys.SCHEMA_INDEX_USAGE view
#22126
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,49 @@ | ||
| // Copyright 2021 PingCAP, Inc. | ||
| // | ||
| // Licensed under the Apache License, Version 2.0 (the "License"); | ||
| // you may not use this file except in compliance with the License. | ||
| // You may obtain a copy of the License at | ||
| // | ||
| // http://www.apache.org/licenses/LICENSE-2.0 | ||
| // | ||
| // Unless required by applicable law or agreed to in writing, software | ||
| // distributed under the License is distributed on an "AS IS" BASIS, | ||
| // See the License for the specific language governing permissions and | ||
| // limitations under the License. | ||
|
|
||
| package sysschema | ||
|
|
||
| var sysSchemaTables = []string{ | ||
| viewUnusedIndexes, | ||
| viewIndexUsage, | ||
| } | ||
|
|
||
| const viewUnusedIndexes = "CREATE VIEW sys." + viewNameUnusedIndexes + | ||
| ` AS SELECT DISTINCT i.table_schema AS table_schema, i.table_name AS table_name, i.key_name AS index_name | ||
|
There was a problem hiding this comment. Why use There was a problem hiding this comment. Consider a situation， table |
||
| FROM information_schema.tidb_indexes AS i | ||
| LEFT JOIN information_schema.tables AS t | ||
| ON t.table_schema = i.table_schema | ||
| AND t.table_name = i.table_name | ||
| LEFT JOIN mysql.schema_index_usage AS u | ||
| ON u.table_id = t.tidb_table_id | ||
| AND u.index_id = i.index_id | ||
| WHERE (u.query_count = 0 OR u.query_count is null) | ||
| AND i.key_name != 'PRIMARY' | ||
| AND i.table_schema not in ('mysql', 'PERFORMANCE_SCHEMA', 'INFORMATION_SCHEMA');` | ||
|
|
||
| const viewIndexUsage = "CREATE VIEW sys." + viewNameIndexUsage + | ||
| ` AS SELECT DISTINCT i.table_schema AS table_schema, | ||
| i.table_name AS table_name, | ||
| i.key_name AS index_name, | ||
| IFNULL(u.query_count, 0) AS query_count, | ||
| IFNULL(u.rows_selected, 0) AS rows_selected, | ||
| u.last_used_at AS last_used_at | ||
| FROM information_schema.tidb_indexes AS i | ||
| LEFT JOIN information_schema.tables AS t | ||
| ON t.table_schema = i.table_schema | ||
| AND t.table_name = i.table_name | ||
| LEFT JOIN mysql.schema_index_usage AS u | ||
| ON u.table_id = t.tidb_table_id | ||
| AND u.index_id = i.index_id | ||
| WHERE i.key_name != 'PRIMARY' | ||
| AND i.table_schema not in ('mysql', 'PERFORMANCE_SCHEMA', 'INFORMATION_SCHEMA');` | ||
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,76 @@ | ||
| // Copyright 2021 PingCAP, Inc. | ||
| // | ||
| // Licensed under the Apache License, Version 2.0 (the "License"); | ||
| // you may not use this file except in compliance with the License. | ||
| // You may obtain a copy of the License at | ||
| // | ||
| // http://www.apache.org/licenses/LICENSE-2.0 | ||
| // | ||
| // Unless required by applicable law or agreed to in writing, software | ||
| // distributed under the License is distributed on an "AS IS" BASIS, | ||
| // See the License for the specific language governing permissions and | ||
| // limitations under the License. | ||
|
|
||
| package sysschema | ||
|
|
||
| import ( | ||
| "fmt" | ||
| "sync" | ||
|
|
||
| "github.com/pingcap/parser" | ||
| "github.com/pingcap/parser/ast" | ||
| "github.com/pingcap/parser/model" | ||
| "github.com/pingcap/parser/mysql" | ||
| "github.com/pingcap/tidb/ddl" | ||
| "github.com/pingcap/tidb/expression" | ||
| "github.com/pingcap/tidb/infoschema" | ||
| "github.com/pingcap/tidb/meta/autoid" | ||
| "github.com/pingcap/tidb/util" | ||
| ) | ||
|
|
||
| var once sync.Once | ||
|
|
||
| // Init register the `sys` views. | ||
| // It should be init(), and the ideal usage should be: | ||
| // | ||
| // import _ "github.com/pingcap/tidb/sysschema" | ||
| // | ||
| // This function depends on plan/core.init(), which initialize the expression.EvalAstExpr function. | ||
| // The initialize order is a problem if init() is used as the function name. | ||
| func Init() { | ||
| initOnce := func() { | ||
| p := parser.New() | ||
| tbls := make([]*model.TableInfo, 0) | ||
| dbID := autoid.SysSchemaDBID | ||
| for _, sql := range sysSchemaTables { | ||
| stmt, err := p.ParseOneStmt(sql, "", "") | ||
| if err != nil { | ||
| panic(err) | ||
| } | ||
| meta, err := ddl.BuildTableInfoFromCreateViewAST(stmt.(*ast.CreateViewStmt)) | ||
| if err != nil { | ||
| panic(err) | ||
| } | ||
| tbls = append(tbls, meta) | ||
| var ok bool | ||
| meta.ID, ok = tableIDMap[meta.Name.O] | ||
| if !ok { | ||
| panic(fmt.Sprintf("get sys table id failed, unknown system table `%v`", meta.Name.O)) | ||
| } | ||
| for i, c := range meta.Columns { | ||
| c.ID = int64(i) + 1 | ||
| } | ||
| } | ||
| dbInfo := &model.DBInfo{ | ||
| ID: dbID, | ||
| Name: util.SysSchemaName, | ||
| Charset: mysql.DefaultCharset, | ||
| Collate: mysql.DefaultCollationName, | ||
| Tables: tbls, | ||
| } | ||
| infoschema.RegisterVirtualTable(dbInfo, tableFromMeta) | ||
| } | ||
| if expression.EvalAstExpr != nil { | ||
| once.Do(initOnce) | ||
| } | ||
| } |
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
How about renaming it to
BuildViewInfoFromASTto correspond toBuildTableInfoFromAST?There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
I don’t think this is a good name, because this function does not build
ViewInfo, butTableInfo.