SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0feafb3867ba8ac10a21438d586cdbb9fa2a30ea7a4a2bc407251bf13f5651d3' 
  AND token = 'WCJsokEj9gZuxDyVpsQm3OHGY1J3LY9vCKl3PUttyY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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