SQL插入新记录如果不存在，否则更新现有记录

如何解决SQL插入新记录如果不存在，否则更新现有记录

我有2个表Staging＆Main Table都有SKU和Price列。记录从那里插入到暂存表中，具体取决于记录，该记录决定是要插入新记录还是更新现有记录。我已经编写了多个查询，这些查询工作正常，但所需时间比平时长。我正在做的是：

Staging Table where data initially inserted into 

+----------+--------------+-----------+-------+---------------------------------------------------------------------------------------------------------------------------+
| indexid  |  Persisted   |    sku    | price |                                                           Logic                                                           |
+----------+--------------+-----------+-------+---------------------------------------------------------------------------------------------------------------------------+
|        1 | No           |   4567456 | 10.99 | This row doesn't exists in main table so need to be inserted and update the persisted to NewProduct                       |
|        2 | No           |   5463454 |  5.99 | This row exists and price matching then this simply need to be updated the persisted to PriceMatched                      |
|        3 | No           |   5645654 |  4.75 | This row exists but price not matching,so new row to be inserted,updated existing record in both tables to PriceUpdated |
|        4 | PriceUpdated |   2222222 |  3.00 |                                                                                                                           |
|        5 | NewProduct   |   5555555 |  4.00 |                                                                                                                           |
|        6 | PriceMatched |   7685765 |  5.00 |                                                                                                                           |
|        7 | PriceUpdated |   6574567 |  3.99 |                                                                                                                           |
+----------+--------------+-----------+-------+---------------------------------------------------------------------------------------------------------------------------+

+---------+--------------+---------+-------+
| indexid |    status    |   sku   | price |
+---------+--------------+---------+-------+
|       1 | Active       | 5635674 | 10.99 |
|       2 | Active       | 5463454 |  5.99 |
|       3 | Active       | 5645654 |  2.75 |
|       4 | PriceUpdated | 2222222 |  3.00 |
|       5 | PriceUpdated | 5555555 |  4.00 |
|       6 | PriceMatched | 7685765 |  5.00 |
|       7 | PriceUpdated | 6574567 |  3.99 |
+---------+--------------+---------+-------+

如果主表中不存在产品，则插入新记录并使用持久化='NewProduct'更新登台表

我从登台表中选择所有记录，其中持久化='否' 然后插入新记录

UPDATE stagingTable SET persisted = 'NewProduct' WHERE indexid = '${indexID}';

否则，检查是否存在现有产品价格匹配，然后持续更新='PriceMatched'

UPDATE stagingTable SET persisted = 'PriceMatched' WHERE indexid = '${indexID}' ;

如果价格不匹配，则将新记录插入主表并更新现有记录状态='PriceUpdated'，并且暂存表='PriceUpdated'

UPDATE mainTable SET productstatus = 'PriceUpdated' WHERE indexid = '${indexID}';
UPDATE stagingTable SET persisted = 'PriceUpdated' WHERE indexid = '${indexID}';

插入工作正常，但更新花费了很长的10000条记录，大约需要15-20分钟。我正在通过批量插入和更新进行插入和更新。

这是我的逻辑