SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd195ee0d1586904eea9dd998ae3ebea6dbeb5e450e0187a245fcf52e86cae79d' 
  AND token = 'RmgbyYNHdHq28M7VayN/bvutg98vxHlLohN0+mBw+NI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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