diff --git a/expression/multi_valued_index_test.go b/expression/multi_valued_index_test.go
index 18ff588eebba..1172d06f7898 100644
--- a/expression/multi_valued_index_test.go
+++ b/expression/multi_valued_index_test.go
@@ -260,6 +260,7 @@ func TestWriteMultiValuedIndex(t *testing.T) {
 	tk.MustExec("insert into t1 values (1, '[\"abc\", \"abc \"]')")
 	tk.MustExec("insert into t1 values (2, '[\"b\"]')")
 	tk.MustExec("insert into t1 values (3, '[\"b   \"]')")
+	tk.MustQuery("select pk from t1 where 'b   ' member of (a)").Check(testkit.Rows("3"))
 
 	t1, err = dom.InfoSchema().TableByName(model.NewCIStr("test"), model.NewCIStr("t1"))
 	require.NoError(t, err)
diff --git a/planner/core/indexmerge_path.go b/planner/core/indexmerge_path.go
index 22c5e75cdd02..8a71e5d5d4f5 100644
--- a/planner/core/indexmerge_path.go
+++ b/planner/core/indexmerge_path.go
@@ -23,6 +23,7 @@ import (
 	"github.com/pingcap/tidb/expression"
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/parser/ast"
+	"github.com/pingcap/tidb/parser/charset"
 	"github.com/pingcap/tidb/parser/model"
 	"github.com/pingcap/tidb/parser/mysql"
 	"github.com/pingcap/tidb/planner/util"
@@ -753,10 +754,12 @@ func (ds *DataSource) prepareCols4MVIndex(mvIndex *model.IndexInfo) (idxCols []*
 		if col == nil { // unexpected, no vir-col on this MVIndex
 			return nil, false
 		}
-		if col.VirtualExpr != nil {
+		if col.GetType().IsArray() {
 			virColNum++
 			col = col.Clone().(*expression.Column)
 			col.RetType = col.GetType().ArrayType() // use the underlying type directly: JSON-ARRAY(INT) --> INT
+			col.RetType.SetCharset(charset.CharsetBin)
+			col.RetType.SetCollate(charset.CollationBin)
 		}
 		idxCols = append(idxCols, col)
 	}
diff --git a/planner/core/testdata/index_merge_suite_out.json b/planner/core/testdata/index_merge_suite_out.json
index d3c3f8b5128a..5810f67c85e9 100644
--- a/planner/core/testdata/index_merge_suite_out.json
+++ b/planner/core/testdata/index_merge_suite_out.json
@@ -234,7 +234,7 @@
         "Plan": [
           "Selection 8.00 root  json_memberof(cast(\"a\", json BINARY), json_extract(test.t.j0, \"$.path_string\"))",
           "└─IndexMerge 10.00 root  type: union",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"a\",\"a\"], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x61,0x61], keep order:false, stats:pseudo",
           "  └─TableRowIDScan(Probe) 10.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
       },
@@ -243,7 +243,7 @@
         "Plan": [
           "Selection 8.00 root  json_memberof(cast(\"a\", json BINARY), json_extract(test.t.j0, \"$.path_string\"))",
           "└─IndexMerge 3.32 root  type: union",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"a\",\"a\"], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x61,0x61], keep order:false, stats:pseudo",
           "  └─Selection(Probe) 3.32 cop[tikv]  lt(test.t.a, 10)",
           "    └─TableRowIDScan 10.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
@@ -252,9 +252,9 @@
         "SQL": "select /*+ use_index_merge(t, j0_string) */ * from t where json_contains((j0->'$.path_string'), '[\"a\", \"b\", \"c\"]')",
         "Plan": [
           "IndexMerge 10.00 root  type: intersection",
-          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"a\",\"a\"], keep order:false, stats:pseudo",
-          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"b\",\"b\"], keep order:false, stats:pseudo",
-          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"c\",\"c\"], keep order:false, stats:pseudo",
+          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x61,0x61], keep order:false, stats:pseudo",
+          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x62,0x62], keep order:false, stats:pseudo",
+          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x63,0x63], keep order:false, stats:pseudo",
           "└─TableRowIDScan(Probe) 10.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
       },
@@ -262,9 +262,9 @@
         "SQL": "select /*+ use_index_merge(t, j0_string) */ * from t where json_contains((j0->'$.path_string'), '[\"a\", \"b\", \"c\"]') and a<10",
         "Plan": [
           "IndexMerge 3.32 root  type: intersection",
-          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"a\",\"a\"], keep order:false, stats:pseudo",
-          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"b\",\"b\"], keep order:false, stats:pseudo",
-          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"c\",\"c\"], keep order:false, stats:pseudo",
+          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x61,0x61], keep order:false, stats:pseudo",
+          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x62,0x62], keep order:false, stats:pseudo",
+          "├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x63,0x63], keep order:false, stats:pseudo",
           "└─Selection(Probe) 3.32 cop[tikv]  lt(test.t.a, 10)",
           "  └─TableRowIDScan 10.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
@@ -274,9 +274,9 @@
         "Plan": [
           "Selection 8.00 root  json_overlaps(json_extract(test.t.j0, \"$.path_string\"), cast(\"[\"a\", \"b\", \"c\"]\", json BINARY))",
           "└─IndexMerge 10.00 root  type: union",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"a\",\"a\"], keep order:false, stats:pseudo",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"b\",\"b\"], keep order:false, stats:pseudo",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"c\",\"c\"], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x61,0x61], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x62,0x62], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x63,0x63], keep order:false, stats:pseudo",
           "  └─TableRowIDScan(Probe) 10.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
       },
@@ -285,9 +285,9 @@
         "Plan": [
           "Selection 8.00 root  json_overlaps(json_extract(test.t.j0, \"$.path_string\"), cast(\"[\"a\", \"b\", \"c\"]\", json BINARY))",
           "└─IndexMerge 3.32 root  type: union",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"a\",\"a\"], keep order:false, stats:pseudo",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"b\",\"b\"], keep order:false, stats:pseudo",
-          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[\"c\",\"c\"], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x61,0x61], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x62,0x62], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 10.00 cop[tikv] table:t, index:j0_string(cast(json_extract(`j0`, _utf8mb4'$.path_string') as char(10) array)) range:[0x63,0x63], keep order:false, stats:pseudo",
           "  └─Selection(Probe) 3.32 cop[tikv]  lt(test.t.a, 10)",
           "    └─TableRowIDScan 10.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
@@ -399,7 +399,7 @@
         "Plan": [
           "Selection 0.00 root  json_memberof(cast(\"3\", json BINARY), json_extract(test.t.j, \"$.str\"))",
           "└─IndexMerge 0.00 root  type: union",
-          "  ├─IndexRangeScan(Build) 0.00 cop[tikv] table:t, index:idx2(a, b, cast(json_extract(`j`, _utf8mb4'$.str') as char(10) array), c) range:[1 2 \"3\" 4,1 2 \"3\" 4], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 0.00 cop[tikv] table:t, index:idx2(a, b, cast(json_extract(`j`, _utf8mb4'$.str') as char(10) array), c) range:[1 2 0x33 4,1 2 0x33 4], keep order:false, stats:pseudo",
           "  └─TableRowIDScan(Probe) 0.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
       },
@@ -408,7 +408,7 @@
         "Plan": [
           "Selection 0.08 root  json_memberof(cast(\"3\", json BINARY), json_extract(test.t.j, \"$.str\"))",
           "└─IndexMerge 0.00 root  type: union",
-          "  ├─IndexRangeScan(Build) 0.00 cop[tikv] table:t, index:idx2(a, b, cast(json_extract(`j`, _utf8mb4'$.str') as char(10) array), c) range:[1 2 \"3\",1 2 \"3\"], keep order:false, stats:pseudo",
+          "  ├─IndexRangeScan(Build) 0.00 cop[tikv] table:t, index:idx2(a, b, cast(json_extract(`j`, _utf8mb4'$.str') as char(10) array), c) range:[1 2 0x33,1 2 0x33], keep order:false, stats:pseudo",
           "  └─TableRowIDScan(Probe) 0.00 cop[tikv] table:t keep order:false, stats:pseudo"
         ]
       },