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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e7a5f4c3a2d6e6cfb66e6cb3426e5077288cfaa43ac2b73726edaee4fdccf657' 
  AND token = 'UKf39DRutOjrNCT4JnlUkpSsRUsR1c6wSgL2OdwoZuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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