Merge pull request #143 from actiontech/issue-142

support general index optimization
actiontech · Dec 13, 2021 · f083dc1 · f083dc1
2 parents b904400 + e2ee0ec
commit f083dc1
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Showing 17 changed files with 2,220 additions and 113 deletions.
diff --git a/go.mod b/go.mod
@@ -4,6 +4,7 @@ go 1.16
 
 require (
 	github.com/DATA-DOG/go-sqlmock v1.5.0
+	github.com/Masterminds/semver/v3 v3.1.1
 	github.com/actiontech/mybatis-mapper-2-sql v0.0.0-20211116051932-8d94d78be18a
 	github.com/agiledragon/gomonkey v2.0.2+incompatible
 	github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751

diff --git a/sqle/driver/mysql/optimizer/index/optimizer.go b/sqle/driver/mysql/optimizer/index/optimizer.go
@@ -7,12 +7,14 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/Masterminds/semver/v3"
 	"github.com/actiontech/sqle/sqle/driver/mysql/executor"
 	"github.com/actiontech/sqle/sqle/driver/mysql/session"
 	"github.com/actiontech/sqle/sqle/driver/mysql/util"
 	indexoptimizer "github.com/actiontech/sqle/sqle/pkg/optimizer/index"
 	"github.com/pingcap/parser/ast"
 	"github.com/pingcap/parser/format"
+	driver "github.com/pingcap/tidb/types/parser_driver"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
@@ -109,7 +111,7 @@ func (o *Optimizer) Optimize(ctx context.Context, selectStmt *ast.SelectStmt) ([
 	for _, tbl := range needOptimizedTables {
 		table, ok := o.tables[tbl]
 		if !ok {
-			// given SQL: select * from t1 join t2, there is not join on condition,
+			// given SQL: select * from t1 join t2, there is no join on condition,
 			continue
 		}
 
@@ -122,8 +124,9 @@ func (o *Optimizer) Optimize(ctx context.Context, selectStmt *ast.SelectStmt) ([
 		} else {
 			result = o.optimizeJoinTable(tbl)
 		}
-
-		results = append(results, result)
+		if result != nil {
+			results = append(results, result)
+		}
 	}
 
 	return results, nil
@@ -247,34 +250,110 @@ func (o *Optimizer) optimizeJoinTable(tbl string) *OptimizeResult {
 
 // doSpecifiedOptimization optimize single table select.
 func (o *Optimizer) doSpecifiedOptimization(ctx context.Context, selectStmt *ast.SelectStmt) (*OptimizeResult, error) {
-	//if selectStmt.Where == nil {
-	//	for _, field := range selectStmt.Fields.Fields {
-	//		tableSource := selectStmt.From.TableRefs.Left.(*ast.TableSource)
-	//		tableName := tableSource.Source.(*ast.TableName).Name.L
-	//
-	//		if field.WildCard == nil {
-	//			switch e := field.Expr.(type) {
-	//			case *ast.AggregateFuncExpr:
-	//				if e.F == ast.AggFuncMin || e.F == ast.AggFuncMax {
-	//					for _, arg := range e.Args {
-	//						if cne, ok := arg.(*ast.ColumnNameExpr); ok {
-	//							return &OptimizeResult{
-	//								TableName:      tableName,
-	//								IndexedColumns: []string{cne.Name.Name.L},
-	//								Reason:         "利用索引有序的性质快速找到记录",
-	//							}, nil
-	//						}
-	//					}
-	//
-	//				}
-	//			}
-	//		}
-	//	}
-	//}
+	if where := selectStmt.Where; where != nil {
+		if boe, ok := where.(*ast.BinaryOperationExpr); ok {
+			// check function in select stmt
+			if fce, ok := boe.L.(*ast.FuncCallExpr); ok {
+				result, err := o.optimizeOnFunctionCallExpression(getTableNameFromSingleSelect(selectStmt), fce)
+				if err != nil {
+					return nil, err
+				}
+				if result != nil {
+					return result, nil
+				}
+			}
+		}
+
+		// check where like 'mike%'
+		if ple, ok := where.(*ast.PatternLikeExpr); ok {
+			if cne, ok := ple.Expr.(*ast.ColumnNameExpr); ok {
+				if ve, ok := ple.Pattern.(*driver.ValueExpr); ok {
+					datum := ve.Datum.GetString()
+					if !strings.HasPrefix(datum, "%") &&
+						!strings.HasPrefix(datum, "_") {
+						return &OptimizeResult{
+							TableName:      getTableNameFromSingleSelect(selectStmt),
+							IndexedColumns: []string{cne.Name.Name.L},
+							Reason:         "为前缀模式匹配添加前缀索引",
+						}, nil
+					}
+				}
+			}
+		}
+	}
+
+	if selectStmt.Where == nil {
+		var cols []string
+		for _, field := range selectStmt.Fields.Fields {
+			if field.Expr != nil {
+				afe, ok := field.Expr.(*ast.AggregateFuncExpr)
+				if !ok {
+					continue
+				}
+				if afe.F == ast.AggFuncMin ||
+					afe.F == ast.AggFuncMax {
+					cne, ok := afe.Args[0].(*ast.ColumnNameExpr)
+					if ok {
+						cols = append(cols, cne.Name.Name.L)
+					}
+				}
+			}
+		}
+		if len(cols) > 0 {
+			return &OptimizeResult{
+				TableName:      getTableNameFromSingleSelect(selectStmt),
+				IndexedColumns: cols,
+				Reason:         "利用索引有序的性质快速找到最值",
+			}, nil
+		}
+	}
 
 	return nil, nil
 }
 
+func (o *Optimizer) optimizeOnFunctionCallExpression(tbl string, fce *ast.FuncCallExpr) (*OptimizeResult, error) {
+	var cols []string
+	for _, arg := range fce.Args {
+		if cne, ok := arg.(*ast.ColumnNameExpr); ok {
+			cols = append(cols, cne.Name.Name.L)
+		}
+	}
+	if len(cols) == 0 {
+		return nil, nil
+	}
+
+	var buf strings.Builder
+	if err := fce.Restore(format.NewRestoreCtx(format.DefaultRestoreFlags, &buf)); err != nil {
+		return nil, errors.Wrap(err, "restore func call expr when do specified optimization")
+	}
+
+	versionWithFlavor, err := o.GetSystemVariable("version")
+	if err != nil {
+		return nil, errors.Wrap(err, "get version when do specified optimization")
+	}
+
+	curVersion, err := semver.NewVersion(versionWithFlavor)
+	if err != nil {
+		return nil, errors.Wrap(err, "parse version when do specified optimization")
+	}
+	if curVersion.LessThan(semver.MustParse("5.7.0")) {
+		return nil, nil
+	}
+	if curVersion.LessThan(semver.MustParse("8.0.13")) {
+		return &OptimizeResult{
+			TableName:      tbl,
+			IndexedColumns: []string{buf.String()},
+			Reason:         "MySQL5.7以上版本需要在虚拟列上创建索引",
+		}, nil
+	}
+
+	return &OptimizeResult{
+		TableName:      tbl,
+		IndexedColumns: []string{buf.String()},
+		Reason:         "MySQL8.0.13以上版本支持直接创建函数索引",
+	}, nil
+}
+
 // doGeneralOptimization optimize single table select.
 func (o *Optimizer) doGeneralOptimization(ctx context.Context, selectStmt *ast.SelectStmt) (*OptimizeResult, error) {
 	generalOptimizer := indexoptimizer.NewOptimizer()