I want to post transfer to other categories.

in category There are too many post.
Change category with SQL
The post on the category I want to transfer to other categories.
Example:
A category post count:900.000
B,C,D,E,F category post count:0
I Want;
A category post count:150.000
B category post count:150.000
C category post count:150.000
D category post count:150.000
E category post count:150.000
F category post count:150.000
how can I do?
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