SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f6e1e23d602936a67120879b0654a7ac0712b2965c154d63748be80d93e8eef' 
  AND token = 'WeCDPv1fNpU8oEnUO4NU8IOpVP2SSA/HlYbN3EdOU2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}