improve understandability

Author: ffffwh

drivers/mysql/mysql/binlog/binlog_reader.go

@@ -474,7 +474,12 @@ func (b *BinlogReader) handleEvent(ev *replication.BinlogEvent, entriesChannel c
 			b.hasBeginQuery = true
 		} else {
 			if strings.ToUpper(query) == "COMMIT" || !b.hasBeginQuery {
-				skipExpandSyntax := !b.mysqlContext.ExpandSyntaxSupport && skipQueryEvent(query)
+				var skipExpandSyntax bool
+				if b.mysqlContext.ExpandSyntaxSupport {
+					skipExpandSyntax = false
+				} else {
+					skipExpandSyntax = isExpandSyntaxQuery(query)
+				}
 
 				ddlInfo, err := resolveDDLSQL(currentSchema, query, b.skipQueryDDL)
 
@@ -1086,7 +1091,7 @@ func (b *BinlogReader) skipQueryDDL(schema string, tableName string) bool {
 	}
 }
 
-func skipQueryEvent(sql string) bool {
+func isExpandSyntaxQuery(sql string) bool {
 	sql = strings.ToLower(sql)
 
 	if strings.HasPrefix(sql, "flush privileges") {

drivers/mysql/mysql/mysqlconfig/types.go

@@ -94,6 +94,9 @@ func (c *Column) ConvertArg(arg interface{}) interface{} {
 			// string, charset conversion
 			if encoding, ok := charsetEncodingMap[c.Charset]; ok {
 				arg, _, _ = transform.String(encoding.NewDecoder(), v)
+				// converting to utf8 encoding
+			} else {
+				// no convertion
 			}
 			return arg
 		}