I want to make a query where I show a result by selecting a city or by selecting a month or search by id_nodo or search by city and month to show me all the nodes in that city that month, I attach an image of my form so that you can understand me better.
SELECT * FROM huawei_gestion_proyectos
WHERE (CIUDAD ='$CIUDAD'
OR MES_DESTINO = '$MES_DESTINO'
OR ID_NODO = '$ID_NODO')
OR (CIUDAD ='$CIUDAD'
AND MES_DESTINO = '$MES_DESTINO')
You can create a base query and concatenate the condition ( WHERE ) based on the values entered by the user in the form.
$consulta = "SELECT * FROM huawei_gestion_proyectos ";
if (isset($ciudad, $mes_destino) && $ciudad != "" && $mes_destino != "") {
$consulta .= "WHERE ciudad = ? AND mes_destino = ?";
} elseif (isset($ciudad) && $ciudad != "") {
$consulta .= "WHERE ciudad = ?";
} elseif (isset($mes_destino) && $mes_destino != "") {
$consulta .= "WHERE mes_destino = ?";
} elseif (isset($id_nodo) && $id_nodo != "") {
$consulta .= "WHERE id_nodo = ?";
} else {
$mensaje = "Debes elegir una ciudad, un mes de destino o escribir el id del nodo";
}