feature: support show table status (#263)

pkg/executor/sharding.go

@@ -176,6 +176,7 @@ func (executor *ShardingExecutor) ExecuteFieldList(ctx context.Context, table, w
 }
 
 func (executor *ShardingExecutor) ExecutorComQuery(ctx context.Context, sql string) (result proto.Result, warn uint16, err error) {
+	proto.WithVariable(ctx, constant.TransactionTimeout, executor.config.TransactionTimeout)
 	spanCtx, span := tracing.GetTraceSpan(ctx, tracing.SHDComQuery)
 	defer span.End()
 
@@ -220,7 +221,15 @@ func (executor *ShardingExecutor) ExecutorComQuery(ctx context.Context, sql stri
 			InsertId:     0,
 		}, 0, nil
 	case *ast.ShowStmt:
-		return executor.executors[0].Query(spanCtx, sql)
+		switch stmt.Tp {
+		case ast.ShowEngines, ast.ShowDatabases, ast.ShowCreateDatabase:
+			return executor.executors[0].Query(spanCtx, sql)
+		}
+		plan, err = executor.optimizer.Optimize(spanCtx, queryStmt)
+		if err != nil {
+			return nil, 0, err
+		}
+		return plan.Execute(spanCtx)
 	case *ast.BeginStmt:
 		tx := group.NewComplexTx(executor.optimizer)
 		executor.localTransactionMap.Store(connectionID, tx)
@@ -267,7 +276,6 @@ func (executor *ShardingExecutor) ExecutorComQuery(ctx context.Context, sql stri
 		if err != nil {
 			return nil, 0, err
 		}
-		proto.WithVariable(spanCtx, constant.TransactionTimeout, executor.config.TransactionTimeout)
 		return plan.Execute(spanCtx)
 	default:
 		txi, ok := executor.localTransactionMap.Load(connectionID)
@@ -279,13 +287,13 @@ func (executor *ShardingExecutor) ExecutorComQuery(ctx context.Context, sql stri
 		if err != nil {
 			return nil, 0, err
 		}
-		proto.WithVariable(spanCtx, constant.TransactionTimeout, executor.config.TransactionTimeout)
 		return plan.Execute(spanCtx)
 	}
 }
 
 func (executor *ShardingExecutor) ExecutorComStmtExecute(
 	ctx context.Context, stmt *proto.Stmt) (result proto.Result, warns uint16, err error) {
+	proto.WithVariable(ctx, constant.TransactionTimeout, executor.config.TransactionTimeout)
 	spanCtx, span := tracing.GetTraceSpan(ctx, tracing.SHDComStmtExecute)
 	defer span.End()
 
@@ -324,7 +332,6 @@ func (executor *ShardingExecutor) ExecutorComStmtExecute(
 	if err != nil {
 		return nil, 0, err
 	}
-	proto.WithVariable(spanCtx, constant.TransactionTimeout, executor.config.TransactionTimeout)
 	return plan.Execute(spanCtx)
 }
 

pkg/optimize/optimize_show_table_status.go

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2022 CECTC, 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package optimize
+
+import (
+	"context"
+
+	"github.com/pkg/errors"
+
+	"github.com/cectc/dbpack/pkg/plan"
+	"github.com/cectc/dbpack/pkg/proto"
+	"github.com/cectc/dbpack/pkg/topo"
+	"github.com/cectc/dbpack/third_party/parser/ast"
+	driver "github.com/cectc/dbpack/third_party/types/parser_driver"
+)
+
+func (o Optimizer) optimizeShowTableStatus(ctx context.Context, stmt *ast.ShowStmt, args []interface{}) (proto.Plan, error) {
+	var (
+		topology *topo.Topology
+		exists   bool
+	)
+
+	if stmt.Tp != ast.ShowTableStatus {
+		return nil, errors.New("statement must be show table status stmt")
+	}
+
+	pattern := stmt.Pattern.Pattern.(*driver.ValueExpr)
+	tableName := pattern.GetDatumString()
+	if topology, exists = o.topologies[tableName]; !exists {
+		return &plan.ShowTableStatusPlan{
+			Stmt:     stmt,
+			Args:     args,
+			Executor: o.executors[0],
+		}, nil
+	} else {
+		table := topology.DBs[o.executors[0].GroupName()][0]
+		pattern.SetValue(table)
+		return &plan.ShowTableStatusPlan{
+			Stmt:     stmt,
+			Args:     args,
+			Executor: o.executors[0],
+		}, nil
+	}
+}

pkg/optimize/optimizer.go

@@ -65,6 +65,11 @@ func (o Optimizer) Optimize(ctx context.Context, stmt ast.StmtNode, args ...inte
 		return o.optimizeDelete(ctx, t, args)
 	case *ast.UpdateStmt:
 		return o.optimizeUpdate(ctx, t, args)
+	case *ast.ShowStmt:
+		switch t.Tp {
+		case ast.ShowTableStatus:
+			return o.optimizeShowTableStatus(ctx, t, args)
+		}
 	}
 	sqlText := proto.SqlText(ctx)
 	return nil, errors.Errorf("unsupported statement type, sql: %s", sqlText)

pkg/plan/query.go

@@ -50,7 +50,7 @@ func (p *QueryDirectlyPlan) Execute(ctx context.Context, hints ...*ast.TableOpti
 		sql string
 		err error
 	)
-	restoreCtx := format.NewRestoreCtx(format.DefaultRestoreFlags|format.RestoreStringWithoutDefaultCharset, &sb)
+	restoreCtx := format.NewRestoreCtx(constant.DBPackRestoreFormat, &sb)
 	if err = p.Stmt.Restore(restoreCtx); err != nil {
 		return nil, 0, errors.WithStack(err)
 	}

pkg/plan/show_table_status.go

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2022 CECTC, 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package plan
+
+import (
+	"context"
+	"strings"
+
+	"github.com/pkg/errors"
+
+	"github.com/cectc/dbpack/pkg/constant"
+	"github.com/cectc/dbpack/pkg/proto"
+	"github.com/cectc/dbpack/third_party/parser/ast"
+	"github.com/cectc/dbpack/third_party/parser/format"
+)
+
+type ShowTableStatusPlan struct {
+	Stmt     *ast.ShowStmt
+	Args     []interface{}
+	Executor proto.DBGroupExecutor
+}
+
+func (p *ShowTableStatusPlan) Execute(ctx context.Context, _ ...*ast.TableOptimizerHint) (proto.Result, uint16, error) {
+	var (
+		sb  strings.Builder
+		sql string
+		err error
+	)
+	restoreCtx := format.NewRestoreCtx(constant.DBPackRestoreFormat, &sb)
+	if err = p.Stmt.Restore(restoreCtx); err != nil {
+		return nil, 0, errors.WithStack(err)
+	}
+	sql = sb.String()
+	commandType := proto.CommandType(ctx)
+	switch commandType {
+	case constant.ComQuery:
+		return p.Executor.Query(ctx, sql)
+	case constant.ComStmtExecute:
+		return p.Executor.PrepareQuery(ctx, sql, p.Args...)
+	default:
+		return nil, 0, nil
+	}
+}

test/shd/sharding_test.go

@@ -239,6 +239,43 @@ func (suite *_ShardingSuite) TestShowCreateDatabase() {
 	}
 }
 
+func (suite *_ShardingSuite) TestShowTableStatus() {
+	rows, err := suite.db.Query("SHOW TABLE STATUS LIKE 'city'")
+	if suite.NoErrorf(err, "show table status error: %v", err) {
+		var (
+			name, engine, version, rowFormat, rowNum, avgRowLength, dataLength, maxDataLength, indexLength, dataFree,
+			autoIncrement, createTime, updateTime, checkTime, collation, checkSum, createOption, comment interface{}
+		)
+		for rows.Next() {
+			err := rows.Scan(&name, &engine, &version, &rowFormat, &rowNum, &avgRowLength, &dataLength, &maxDataLength,
+				&indexLength, &dataFree, &autoIncrement, &createTime, &updateTime, &checkTime, &collation, &checkSum,
+				&createOption, &comment)
+			suite.NoError(err)
+			suite.T().Log("table city:")
+			suite.T().Logf("%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s",
+				name, engine, version, rowFormat, rowNum, avgRowLength, dataLength, maxDataLength, indexLength, dataFree,
+				autoIncrement, createTime, updateTime, checkTime, collation, checkSum, createOption, comment)
+		}
+	}
+	rows, err = suite.db.Query("SHOW TABLE STATUS LIKE 'countrylanguage'")
+	if suite.NoErrorf(err, "show table status error: %v", err) {
+		var (
+			name, engine, version, rowFormat, rowNum, avgRowLength, dataLength, maxDataLength, indexLength, dataFree,
+			autoIncrement, createTime, updateTime, checkTime, collation, checkSum, createOption, comment interface{}
+		)
+		for rows.Next() {
+			err := rows.Scan(&name, &engine, &version, &rowFormat, &rowNum, &avgRowLength, &dataLength, &maxDataLength,
+				&indexLength, &dataFree, &autoIncrement, &createTime, &updateTime, &checkTime, &collation, &checkSum,
+				&createOption, &comment)
+			suite.NoError(err)
+			suite.T().Log("table countrylanguage:")
+			suite.T().Logf("%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s	%s",
+				name, engine, version, rowFormat, rowNum, avgRowLength, dataLength, maxDataLength, indexLength, dataFree,
+				autoIncrement, createTime, updateTime, checkTime, collation, checkSum, createOption, comment)
+		}
+	}
+}
+
 func (suite *_ShardingSuite) TestDeleteCity() {
 	result, err := suite.db.Exec(deleteCity, 10, 20)
 	suite.Assert().Nil(err)