diff --git a/helpers.go b/helpers.go
index f59db48b..7efa7294 100644
--- a/helpers.go
+++ b/helpers.go
@@ -490,9 +490,8 @@ func genCols(table *core.Table, session *Session, bean interface{}, useCol bool,
 	args := make([]interface{}, 0, len(table.ColumnsSeq()))
 
 	for _, col := range table.Columns() {
-		lColName := strings.ToLower(col.Name)
 		if useCol && !col.IsVersion && !col.IsCreated && !col.IsUpdated {
-			if _, ok := session.Statement.columnMap[lColName]; !ok {
+			if _, ok := getFlagForColumn(session.Statement.columnMap, col); !ok {
 				continue
 			}
 		}
@@ -528,18 +527,18 @@ func genCols(table *core.Table, session *Session, bean interface{}, useCol bool,
 		}
 
 		if session.Statement.ColumnStr != "" {
-			if _, ok := session.Statement.columnMap[lColName]; !ok {
+			if _, ok := getFlagForColumn(session.Statement.columnMap, col); !ok {
 				continue
 			}
 		}
 		if session.Statement.OmitStr != "" {
-			if _, ok := session.Statement.columnMap[lColName]; ok {
+			if _, ok := getFlagForColumn(session.Statement.columnMap, col); ok {
 				continue
 			}
 		}
 
 		// !evalphobia! set fieldValue as nil when column is nullable and zero-value
-		if _, ok := session.Statement.nullableMap[lColName]; ok {
+		if _, ok := getFlagForColumn(session.Statement.nullableMap, col); ok {
 			if col.Nullable && isZero(fieldValue.Interface()) {
 				var nilValue *int
 				fieldValue = reflect.ValueOf(nilValue)
@@ -578,3 +577,23 @@ func genCols(table *core.Table, session *Session, bean interface{}, useCol bool,
 func indexName(tableName, idxName string) string {
 	return fmt.Sprintf("IDX_%v_%v", tableName, idxName)
 }
+
+func getFlagForColumn(m map[string]bool, col *core.Column) (val bool, has bool) {
+
+	if len(m) == 0 {
+		return false, false
+	}
+
+	n := len(col.Name)
+
+	for mk := range m {
+		if len(mk) != n {
+			continue
+		}
+		if strings.EqualFold(mk, col.Name) {
+			return m[mk], true
+		}
+	}
+
+	return false, false
+}
diff --git a/session.go b/session.go
index 10033313..8f325000 100644
--- a/session.go
+++ b/session.go
@@ -2318,12 +2318,12 @@ func (session *Session) innerInsertMulti(rowsSlicePtr interface{}) (int64, error
 					continue
 				}
 				if session.Statement.ColumnStr != "" {
-					if _, ok := session.Statement.columnMap[strings.ToLower(col.Name)]; !ok {
+					if _, ok := getFlagForColumn(session.Statement.columnMap, col); !ok {
 						continue
 					}
 				}
 				if session.Statement.OmitStr != "" {
-					if _, ok := session.Statement.columnMap[strings.ToLower(col.Name)]; ok {
+					if _, ok := getFlagForColumn(session.Statement.columnMap, col); ok {
 						continue
 					}
 				}
@@ -2373,12 +2373,12 @@ func (session *Session) innerInsertMulti(rowsSlicePtr interface{}) (int64, error
 					continue
 				}
 				if session.Statement.ColumnStr != "" {
-					if _, ok := session.Statement.columnMap[strings.ToLower(col.Name)]; !ok {
+					if _, ok := getFlagForColumn(session.Statement.columnMap, col); !ok {
 						continue
 					}
 				}
 				if session.Statement.OmitStr != "" {
-					if _, ok := session.Statement.columnMap[strings.ToLower(col.Name)]; ok {
+					if _, ok := getFlagForColumn(session.Statement.columnMap, col); ok {
 						continue
 					}
 				}
diff --git a/statement.go b/statement.go
index 07fa14bf..02c9f598 100644
--- a/statement.go
+++ b/statement.go
@@ -273,9 +273,8 @@ func buildUpdates(engine *Engine, table *core.Table, bean interface{},
 
 		requiredField := useAllCols
 		includeNil := useAllCols
-		lColName := strings.ToLower(col.Name)
 
-		if b, ok := mustColumnMap[lColName]; ok {
+		if b, ok := getFlagForColumn(mustColumnMap, col); ok {
 			if b {
 				requiredField = true
 			} else {
@@ -284,7 +283,7 @@ func buildUpdates(engine *Engine, table *core.Table, bean interface{},
 		}
 
 		// !evalphobia! set fieldValue as nil when column is nullable and zero-value
-		if b, ok := nullableMap[lColName]; ok {
+		if b, ok := getFlagForColumn(nullableMap, col); ok {
 			if b && col.Nullable && isZero(fieldValue.Interface()) {
 				var nilValue *int
 				fieldValue = reflect.ValueOf(nilValue)
@@ -533,7 +532,8 @@ func buildConds(engine *Engine, table *core.Table, bean interface{},
 
 		fieldType := reflect.TypeOf(fieldValue.Interface())
 		requiredField := useAllCols
-		if b, ok := mustColumnMap[strings.ToLower(col.Name)]; ok {
+
+		if b, ok := getFlagForColumn(mustColumnMap, col); ok {
 			if b {
 				requiredField = true
 			} else {
@@ -993,7 +993,7 @@ func (statement *Statement) genColumnStr() string {
 	for _, col := range columns {
 
 		if statement.OmitStr != "" {
-			if _, ok := statement.columnMap[strings.ToLower(col.Name)]; ok {
+			if _, ok := getFlagForColumn(statement.columnMap, col); ok {
 				continue
 			}
 		}
diff --git a/statement_test.go b/statement_test.go
index 3929a76e..91de19bd 100644
--- a/statement_test.go
+++ b/statement_test.go
@@ -6,6 +6,8 @@ import (
 	"testing"
 	"time"
 
+	"strings"
+
 	"github.com/go-xorm/core"
 )
 
@@ -83,6 +85,70 @@ func BenchmarkColumnsStringGeneration(b *testing.B) {
 	}
 }
 
+func BenchmarkGetFlagForColumnWithICKey_ContainsKey(b *testing.B) {
+
+	b.StopTimer()
+
+	mapCols := make(map[string]bool)
+	cols := []*core.Column{
+		&core.Column{Name: `ID`},
+		&core.Column{Name: `IsDeleted`},
+		&core.Column{Name: `Caption`},
+		&core.Column{Name: `Code1`},
+		&core.Column{Name: `Code2`},
+		&core.Column{Name: `Code3`},
+		&core.Column{Name: `ParentID`},
+		&core.Column{Name: `Latitude`},
+		&core.Column{Name: `Longitude`},
+	}
+
+	for _, col := range cols {
+		mapCols[strings.ToLower(col.Name)] = true
+	}
+
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+
+		for _, col := range cols {
+
+			if _, ok := getFlagForColumn(mapCols, col); !ok {
+				b.Fatal("Unexpected result")
+			}
+		}
+	}
+}
+
+func BenchmarkGetFlagForColumnWithICKey_EmptyMap(b *testing.B) {
+
+	b.StopTimer()
+
+	mapCols := make(map[string]bool)
+	cols := []*core.Column{
+		&core.Column{Name: `ID`},
+		&core.Column{Name: `IsDeleted`},
+		&core.Column{Name: `Caption`},
+		&core.Column{Name: `Code1`},
+		&core.Column{Name: `Code2`},
+		&core.Column{Name: `Code3`},
+		&core.Column{Name: `ParentID`},
+		&core.Column{Name: `Latitude`},
+		&core.Column{Name: `Longitude`},
+	}
+
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+
+		for _, col := range cols {
+
+			if _, ok := getFlagForColumn(mapCols, col); ok {
+				b.Fatal("Unexpected result")
+			}
+		}
+	}
+}
+
 type TestType struct {
 	ID        int64   `xorm:"ID PK"`
 	IsDeleted bool    `xorm:"IsDeleted"`