SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecefc2d75b72487851fa80109f48304f779ef2e23362a101d1f2ea488ff7dce8' 
  AND token = 'Pg3DFg0uvW3++Gh4sCb+GSQKZ2V8yEHRI0IXo0DRuF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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