Consulta 1
Código MySQL :
SELECT * FROM tbl1 INNER JOIN tbl2 ON tbl1.Id1 = tbl2.Id1 AND tbl1.activo = 1 INNER JOIN tbl3 ON tbl2.Id2 = tbl3.Id2 INNER JOIN tbl4 ON tbl3.Id3 = tbl4.Id3 INNER JOIN tbl5 ON tbl4.Id4 = tbl5.Id4 INNER JOIN tbl6 ON tbl5.Id5 = tbl6.Id5
Consulta 2
Código MySQL :
SELECT * FROM tbl1 INNER JOIN tbl2 ON tbl1.Id1 = tbl2.Id1 INNER JOIN tbl3 ON tbl2.Id2 = tbl3.Id2 INNER JOIN tbl4 ON tbl3.Id3 = tbl4.Id3 INNER JOIN tbl5 ON tbl4.Id4 = tbl5.Id4 INNER JOIN tbl6 ON tbl5.Id5 = tbl6.Id5 WHERE tbl1.activo = 1
Consulta 3
Código MySQL :
SELECT * FROM ( SELECT * FROM tbl1 WHERE activo = 1 ) AS tbl1 INNER JOIN tbl2 ON tbl1.Id1 = tbl2.Id1 INNER JOIN tbl3 ON tbl2.Id2 = tbl3.Id2 INNER JOIN tbl4 ON tbl3.Id3 = tbl4.Id3 INNER JOIN tbl5 ON tbl4.Id4 = tbl5.Id4 INNER JOIN tbl6 ON tbl5.Id5 = tbl6.Id5
Nota: Para hacer el codigo mas entendible omiti la seleccion de las columnas y coloque "SELECT * FROM"
Según uds. cual de estas tres consulta es la mas optima, yo me inclino entre la 1 y la 3.-
