From b0d9934fb05a0b61878eb72a0bd437388160c1b0 Mon Sep 17 00:00:00 2001
From: Zhuomin Liu <lzmhhh123@gmail.com>
Date: Tue, 15 Dec 2020 12:12:55 +0800
Subject: [PATCH] types: fix compare float64 with float64 in json (#21709)

Signed-off-by: lzmhhh123 <lzmhhh123@gmail.com>
---
 expression/integration_test.go |  7 +++++++
 types/json/binary_functions.go | 12 +++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/expression/integration_test.go b/expression/integration_test.go
index e6b4e0680fe14..0d5753ba176a1 100644
--- a/expression/integration_test.go
+++ b/expression/integration_test.go
@@ -4404,6 +4404,13 @@ func (s *testIntegrationSuite) TestFuncJSON(c *C) {
 
 	// #16267
 	tk.MustQuery(`select json_array(922337203685477580) =  json_array(922337203685477581);`).Check(testkit.Rows("0"))
+
+	// #10461
+	tk.MustExec("drop table if exists tx1")
+	tk.MustExec("create table tx1(id int key, a double, b double, c double, d double)")
+	tk.MustExec("insert into tx1 values (1, 0.1, 0.2, 0.3, 0.0)")
+	tk.MustQuery("select a+b, c from tx1").Check(testkit.Rows("0.30000000000000004 0.3"))
+	tk.MustQuery("select json_array(a+b) = json_array(c) from tx1").Check(testkit.Rows("0"))
 }
 
 func (s *testIntegrationSuite) TestColumnInfoModified(c *C) {
diff --git a/types/json/binary_functions.go b/types/json/binary_functions.go
index 478aea2d2aded..30133c6e7b5ab 100644
--- a/types/json/binary_functions.go
+++ b/types/json/binary_functions.go
@@ -647,6 +647,16 @@ func compareInt64(x int64, y int64) int {
 	return 1
 }
 
+func compareFloat64(x float64, y float64) int {
+	if x < y {
+		return -1
+	} else if x == y {
+		return 0
+	}
+
+	return 1
+}
+
 func compareUint64(x uint64, y uint64) int {
 	if x < y {
 		return -1
@@ -712,7 +722,7 @@ func CompareBinary(left, right BinaryJSON) int {
 			case TypeCodeUint64:
 				cmp = compareFloat64Uint64(left.GetFloat64(), right.GetUint64())
 			case TypeCodeFloat64:
-				cmp = compareFloat64PrecisionLoss(left.GetFloat64(), right.GetFloat64())
+				cmp = compareFloat64(left.GetFloat64(), right.GetFloat64())
 			}
 		case TypeCodeString:
 			cmp = bytes.Compare(left.GetString(), right.GetString())