Select all records from one table, and count records in another table

please try like this
Code:
SELECT master_adverse_event.adverse_event_id, master_adverse_event.adverse_event_name,SUM(IF(transaction_adverse_event.adverse_event_id IS NULL, 0, 1)) AS total FROM master_adverse_event LEFT JOIN transaction_adverse_event ON master_adverse_event.adverse_event_id = transaction_adverse_event.adverse_event_id WHERE master_adverse_event.adverse_event_id
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