QUERY PLAN
Delete on tbl_contact_attend_pre_sales (cost=0.28..8.30 rows=1 width=6)
-> Index Scan using tbl_contact_attend_pre_sales_pkey on tbl_contact_attend_pre_sales (cost=0.28..8.30 rows=1 width=6)
Index Cond: (pre_sales_id = 1838)