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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a8ae3946d0b608f3ee5d4645d4581d3724af9f0f790c7dc791df511d1eb4a5d' 
  AND token = 'tN3N0y4DjEH8SZB3IxmTc1hI6ZUHTPz01J3KMo+x6kg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}