Help with Create View
My View is:
CREATE VIEW `vista_global` AS SELECT TC.nombreCentro, TP.Profesores, TA.Alumnos
FROM tbl_centros TC
LEFT JOIN (
SELECT centro, COUNT( * ) Profesores
FROM tbl_profesores
GROUP BY centro
)TP ON TC.idCentro = TP.centro
LEFT J开发者_高级运维OIN (
SELECT centro, COUNT( * ) Alumnos
FROM tbl_alumnos
GROUP BY centro
)TA ON TC.idCentro = TA.centro
But this not run well. Do you can help me, please?
You don't have to use subqueries:
CREATE VIEW `vista_global` AS
SELECT TC.nombreCentro,
COUNT(TP.centro) Profesores,
COUNT(TA.centro) Alumnos
FROM tbl_centros TC
LEFT JOIN tbl_profesores TP ON TC.idCentro = TP.centro
LEFT JOIN tbl_alumnos TQ ON TC.idCentro = TA.centro
GROUP BY TC.nombreCentro
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