我在使用LIKE的数据库查询中遇到问题

请帮助我。我想要的是，我想在Table1中将所有prefixNo插入到ContactNo的table2的prefixNo中。因此，PrefixNo中Table2中的所有NULL将在table1中的prefixNo中更改为3个字符。

Pls help me. what i want is, I want to Insert all the prefixNo in Table1 to prefixNo of table2 base on the ContactNo. So all the NULL in Table2 in PrefixNo will be change into 3 character in prefixNo in table1.

UPDATE  table2 SET  prefixNo = (SELECT prefixNo WHERE Table1 LIKE prefixNo)  WHERE contactno LIKE (SELECT prefixNo WHERE Table1 LIKE prefixNo) ORDER BY prefixNo

它不起作用。我尝试不同类型的编码，但它不起作用。 :(。有什么问题？请帮助我。



table1

It's not working. I try different type of coding but it doesn't work. :(. what is problem? pls help me.

table1

id  |    prefixNo
1   |   910
2   |   922
3   |   920
4   |   929
5   |   930
6   |   932
7   |   933

table2

table2

id  |   prefixNo|   ContactNo
1   |   NULL    |   9309556384
2   |   NULL    |   9307815328
3   |   NULL    |   9334489301
4   |   NULL    |   9330000024
5   |   NULL    |   9108456218
6   |   NULL    |   9305789621
7   |   NULL    |   9335554868
8   |   NULL    |   9224813354
9   |   NULL    |   9222224568
10  |   NULL    |   9105789545

ok。所以这是我要显示的输出



输出：

ok. so this is the output i want to display

OUTPUT:

Table 2
id  |   prefixNo|   ContactNo
1   |   930 |   9309556384
2   |   930 |   9307815328
3   |   933 |   9334489301
4   |   933 |   9330000024
5   |   910 |   9108456218
6   |   930 |   9305789621
7   |   933 |   9335554868
8   |   922 |   9224813354
9   |   922 |   9222224568
10  |   910 |   9105789545