Query to read transaction state

go/test/endtoend/transaction/twopc/twopc_test.go

@@ -19,8 +19,10 @@ package transaction
 import (
 	"context"
 	_ "embed"
+	"fmt"
 	"reflect"
 	"sort"
+	"strings"
 	"sync"
 	"testing"
 	"time"
@@ -849,6 +851,19 @@ func TestDTResolveAfterTransactionRecord(t *testing.T) {
 	_, err = conn.Execute(newCtx, "commit", nil)
 	require.ErrorContains(t, err, "Fail After TR created")
 
+	t.Run("ReadTransactionState", func(t *testing.T) {
+		errStr := err.Error()
+		indx := strings.Index(errStr, "Fail")
+		require.Greater(t, indx, 0)
+		dtid := errStr[0 : indx-2]
+		res, err := conn.Execute(context.Background(), fmt.Sprintf(`show transaction status for '%v'`, dtid), nil)
+		require.NoError(t, err)
+		resStr := fmt.Sprintf("%v", res.Rows)
+		require.Contains(t, resStr, `[[VARCHAR("ks:80-`)
+		require.Contains(t, resStr, `VARCHAR("PREPARE") DATETIME("`)
+		require.Contains(t, resStr, `+0000 UTC") VARCHAR("ks:40-80")]]`)
+	})
+
 	// Below check ensures that the transaction is resolved by the resolver on receiving unresolved transaction signal from MM.
 	tableMap := make(map[string][]*querypb.Field)
 	dtMap := make(map[string]string)

go/vt/sqlparser/ast.go

@@ -1671,6 +1671,11 @@ type (
 		Filter  *ShowFilter
 	}
 
+	// ShowTransactionStatus is used to see the status of a distributed transaction in progress.
+	ShowTransactionStatus struct {
+		TransactionID string
+	}
+
 	// ShowCreate is of ShowInternal type, holds SHOW CREATE queries.
 	ShowCreate struct {
 		Command ShowCommandType
@@ -1683,9 +1688,10 @@ type (
 	}
 )
 
-func (*ShowBasic) isShowInternal()  {}
-func (*ShowCreate) isShowInternal() {}
-func (*ShowOther) isShowInternal()  {}
+func (*ShowBasic) isShowInternal()             {}
+func (*ShowCreate) isShowInternal()            {}
+func (*ShowOther) isShowInternal()             {}
+func (*ShowTransactionStatus) isShowInternal() {}
 
 // InsertRows represents the rows for an INSERT statement.
 type InsertRows interface {

go/vt/sqlparser/ast_format.go

@@ -2149,6 +2149,10 @@ func (node *ShowBasic) Format(buf *TrackedBuffer) {
 	buf.astPrintf(node, "%v", node.Filter)
 }
 
+func (node *ShowTransactionStatus) Format(buf *TrackedBuffer) {
+	buf.astPrintf(node, "show transaction status for '%#s'", node.TransactionID)
+}
+
 // Format formats the node.
 func (node *ShowCreate) Format(buf *TrackedBuffer) {
 	buf.astPrintf(node, "show%s %v", node.Command.ToString(), node.Op)

go/vt/sqlparser/parse_test.go

@@ -2428,6 +2428,17 @@ var (
 		input: "show vitess_migrations like '9748c3b7_7fdb_11eb_ac2c_f875a4d24e90'",
 	}, {
 		input: "show vitess_migration '9748c3b7_7fdb_11eb_ac2c_f875a4d24e90' logs",
+	}, {
+		input: "show transaction status for 'ks:-80:232323238342'",
+	}, {
+		input:  "show transaction status for \"ks:-80:232323238342\"",
+		output: "show transaction status for 'ks:-80:232323238342'",
+	}, {
+		input:  "show transaction status 'ks:-80:232323238342'",
+		output: "show transaction status for 'ks:-80:232323238342'",
+	}, {
+		input:  "show transaction status \"ks:-80:232323238342\"",
+		output: "show transaction status for 'ks:-80:232323238342'",
 	}, {
 		input: "revert vitess_migration '9748c3b7_7fdb_11eb_ac2c_f875a4d24e90'",
 	}, {