Thanks for your response. This is a full copy of the error:

Discount Coupons Product/Category Restrictions
Category Restrictions
1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-0, MAX_DISPLAY_RESTRICT_ENTRIES' at line 1
in:
[select * from coupon_restrict where coupon_id = '56' and category_id != '0' limit -0, MAX_DISPLAY_RESTRICT_ENTRIES]
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