From e579d1cde98c4971ea4bca966a2eb7ccde75445e Mon Sep 17 00:00:00 2001
From: ti-srebot <66930949+ti-srebot@users.noreply.github.com>
Date: Fri, 12 Mar 2021 19:36:56 +0800
Subject: [PATCH] planner: fixed a bug that prevented SPM from taking effect
 (#23197) (#23209)

---
 bindinfo/bind_test.go | 14 ++++++++++++++
 planner/optimize.go   | 14 ++------------
 2 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/bindinfo/bind_test.go b/bindinfo/bind_test.go
index 5daecc922a765..d0df1d6f54591 100644
--- a/bindinfo/bind_test.go
+++ b/bindinfo/bind_test.go
@@ -1865,3 +1865,17 @@ func (s *testSuite) TestCaptureWithZeroSlowLogThreshold(c *C) {
 	c.Assert(len(rows), Equals, 1)
 	c.Assert(rows[0][0], Equals, "select * from test . t")
 }
+
+func (s *testSuite) TestSPMWithoutUseDatabase(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk1 := testkit.NewTestKit(c, s.store)
+	s.cleanBindingEnv(tk)
+	s.cleanBindingEnv(tk1)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t(a int, b int, key(a))")
+	tk.MustExec("create global binding for select * from t using select * from t force index(a)")
+
+	err := tk1.ExecToErr("select * from t")
+	c.Assert(err, ErrorMatches, "*No database selected")
+}
diff --git a/planner/optimize.go b/planner/optimize.go
index 0eefceffc2262..bf08b87813124 100644
--- a/planner/optimize.go
+++ b/planner/optimize.go
@@ -273,12 +273,7 @@ func extractSelectAndNormalizeDigest(stmtNode ast.StmtNode, specifiledDB string)
 		switch x.Stmt.(type) {
 		case *ast.SelectStmt, *ast.DeleteStmt, *ast.UpdateStmt, *ast.InsertStmt:
 			plannercore.EraseLastSemicolon(x)
-			var normalizeExplainSQL string
-			if specifiledDB != "" {
-				normalizeExplainSQL = parser.Normalize(utilparser.RestoreWithDefaultDB(x, specifiledDB))
-			} else {
-				normalizeExplainSQL = parser.Normalize(x.Text())
-			}
+			normalizeExplainSQL := parser.Normalize(utilparser.RestoreWithDefaultDB(x, specifiledDB))
 			idx := int(0)
 			switch n := x.Stmt.(type) {
 			case *ast.SelectStmt:
@@ -308,12 +303,7 @@ func extractSelectAndNormalizeDigest(stmtNode ast.StmtNode, specifiledDB string)
 		if len(x.Text()) == 0 {
 			return x, "", ""
 		}
-		var normalizedSQL, hash string
-		if specifiledDB != "" {
-			normalizedSQL, hash = parser.NormalizeDigest(utilparser.RestoreWithDefaultDB(x, specifiledDB))
-		} else {
-			normalizedSQL, hash = parser.NormalizeDigest(x.Text())
-		}
+		normalizedSQL, hash := parser.NormalizeDigest(utilparser.RestoreWithDefaultDB(x, specifiledDB))
 		return x, normalizedSQL, hash
 	}
 	return nil, "", ""