SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6925ae80c6f2e9ac2c3043f64bcc252b238bb5c836f76f2fc33931d69262ba5b' 
  AND token = 'Q8mqQgquwuRwbQyD0y/JzOYPp/cAX7cds8nwOADNKho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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