!70 merge

Merge pull request !70 from AE86/V_1.0.0_Beta

dbsyncer-connector/src/main/java/org/dbsyncer/connector/database/sqlbuilder/SqlBuilderUpdate.java

@@ -1,5 +1,6 @@
 package org.dbsyncer.connector.database.sqlbuilder;
 
+import org.dbsyncer.common.util.StringUtil;
 import org.dbsyncer.connector.config.SqlBuilderConfig;
 import org.dbsyncer.connector.database.AbstractSqlBuilder;
 import org.dbsyncer.connector.model.Field;
@@ -25,9 +26,6 @@ public class SqlBuilderUpdate extends AbstractSqlBuilder {
         for (int i = 0; i < size; i++) {
             // skip pk
             if (fields.get(i).isPk()) {
-                if (i == end) {
-                    sql.deleteCharAt(sql.length() - 1);
-                }
                 continue;
             }
 
@@ -37,6 +35,13 @@ public class SqlBuilderUpdate extends AbstractSqlBuilder {
                 sql.append(",");
             }
         }
+
+        // 删除多余的符号
+        int last = sql.length() - 1;
+        if(StringUtil.equals(",", sql.substring(last))){
+            sql.deleteCharAt(last);
+        }
+
         // UPDATE "USER" SET "USERNAME"=?,"AGE"=? WHERE "ID"=?
         sql.append(" WHERE ").append(quotation).append(config.getPk()).append(quotation).append("=?");
         return sql.toString();