SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc0b038ac7e3881440a7fa76437a77543e04c2102fac8a728b63342ff586ba9d' 
  AND token = 'oot/ZWFwHxgUpPtqqQ1ws6KoeqJyCU/BRbvq4S/H1l0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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