mysql – How to make an UPDATE in a query that is conditioned by a WHERE and in turn by a limited by LIMIT?

Question:

I need help with a query limit. What I am trying to do is update a table of Students so that each student is automatically assigned a section according to a limit set by the admin user.

I have already tried to use the between function but I failed!

// IT DOES NOT WORK LIKE THIS

$consulta = "UPDATE `estudiantes` SET `seccion` = 'A' 
WHERE `EtapaGradoGrupo` = '5° Año' LIMIT 20,15; "; 

// SO IT WORKS but it updates all the registers from 1 to 20 and I want it to start updating from register 15 to register 20, that is, only 5 not the 20

$consulta = "UPDATE `estudiantes` SET `seccion` = 'A' 
WHERE `EtapaGradoGrupo` = '5° Año' LIMIT 20;"; 

I would like that Each student of a specific "Year N°" update their section to "A", "B", "C"… But in the query select Only the students of said "Year N°" Limited By the number of students per section that the user selected Note: The query works only when the limit has a single parameter but when I add the second parameter to include the position from which the section will start updating it gives me an IMG error with the error what gives me MySql

---

Try doing the following NOTE: I am learning how to use StackOverflow

require("datos_de_conexion.php");
$conexion = mysqli_connect( $direccion , $usuario , $password ,$servidor);
mysqli_set_charset($conexion ,"utf8");

$consulta = "SELECT*FROM`estudiantes`WHERE`Etapa/Grado/Grupo`='5°Año'LIMIT 
5, 5";
$resultado = mysqli_query( $conexion , $consulta );

while( $fila = mysqli_fetch_array( $resultado , MYSQLI_ASSOC ) ){

$IDE = $fila["ExpedienteN°"];

$Actualizar = "UPDATE `estudiantes` SET `seccion` = 'Z' WHERE 
`ExpedienteN°` = $IDE;";
$resultado_2 = mysqli_query( $conexion , $Actualizar );

}

echo "Fueron afectadas " . $filasAfectadas = mysqli_affected_rows( $conexion 
);

*Generates the query perfectly BUT when I execute the query inside the while it only affects 1 row, that is, the cycle should do 5 turns but it only does 1 if I print on the screen this is what appears:

UPDATE `estudiantes` SET `seccion` = 'Z' WHERE `ExpedienteN°` = 6; 
UPDATE `estudiantes` SET `seccion` = 'Z' WHERE `ExpedienteN°` = 7; 
UPDATE `estudiantes` SET `seccion` = 'Z' WHERE `ExpedienteN°` = 8; 
UPDATE `estudiantes` SET `seccion` = 'Z' WHERE `ExpedienteN°` = 9; 
UPDATE `estudiantes` SET `seccion` = 'Z' WHERE `ExpedienteN°` = 10; 
Fueron afectadas -1

Since the queries are generated correctly in each cycle, but only the first one with ID = 6 is executed!

Answer:

You could try using BETWEEN which works for:

Perform your update with records from a specific data range, in this case all id starting from 15 to 20.

A) Yes:

$consulta = "UPDATE `estudiantes` SET `seccion` = 'A' 
             WHERE `EtapaGradoGrupo` = '5° Año' 
             AND id BETWEEN 15 AND 20"; 

If you now do:

SELECT * FROM estudiantes 
LIMIT 14, 20;

It will show you all the records from 15 to 20 with the updated values ​​with the updated seccion column.