Mysql:Query for the table as bellow
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I have a table as bellow

**id Homephone**

1   454454125

2   47872154587

3   128795423

4   148784474

like this i have 40,000 rows

Here i want to replace Homephone values as bellow 

454-454-125 

478-721-545-87

128-795-423

148-784-474

ie after every 3 numbers i want '-'(hyphon)
how to do this in mysql

Thanking you in advance