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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c21f33531afecebc20ffb167ec38230dc071577ebb35ba7d132b0d1d86f9fa7e' 
  AND token = 'dh/prmSlPHcZ8ohM9ELr9rDY7VUcwwrefmrzDkfSzfM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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