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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a5b13a781e5e6a97c9fdebef3b3e311c04a67cb9cb2ab9981447fdc2b55908d0' 
  AND token = 'SE3LdSzOoP8MU3x9T9EyHVZ0nkVBrcn2HNxqatLdL/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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