1. Multitenant Applications con GeneXus Federico Azzato, Equipo de Desarrollo fazzato@artech.com.uy

2. ¿Que es una aplicación Multitenant? Aplicación diseñada para soportar múltiples clientes Compartir recursos de instalación Reducir costos Ej: GXportal, GXserver, Wiki, Blog, etc

3. ¿Cómo se diseña una aplicación Multitenant? El principal problema está en los datos No hay UNA respuesta Hay varias técnicas que hacen que la aplicación sea multitenant

4. ¿Cómo se diseña una aplicación Multitenant? Separated DB SeparatedSchema SharedSchema

5. Separated DB Enfoque más simple Se comparte la instalación y los programas instalados Facilita backups individuales Aumentan costos de mantenimiento Apropiada para un número reducido de tenants

6. SeparatedSchema Enfoque relativamente simple Cada tenant tiene sus tablas en su propio esquema en la misma DB CREATE SCHEMATenantNSchemaAUTHORIZATION TenantN ALTER USERTenantNWITH DEFAULT_SCHEMA = TenantNSchema Aumenta complejidad de administración de datos Apropiada para un número reducido de tablas (<100)

7. SharedSchema Los tenants comparten las tablas de la base de datos Cada tenant tiene su ID, y las consultas filtran los registros por ese ID SELECT * FROM Customer WHERETenantId = @TenantId Aumenta el costo de desarrollo ¿Qué sucede si me olvido de filtrar por TenantId? Mayor escalabilidad

8. ¿Cuál es la mejor? Cada una tiene sus ventajas y desventajas Cada una es la más apropiada en determinado contexto

9. ¿Quién lo dijo? “… La implementación sharedschema en 3 pasos es una roca!” @FedeAzzato Encontramos una solución para agregar el TenantId en todas las tablas, con cero impacto en tiempo de desarrollo Los programas generados no cambian en nada

10. Usando SQL Views y Triggers Los programas generados no se enteran que existe un campo TenantId Los SELECT, INSERT, UPDATEy DELETE se hacen contra las vistas Lo único que cambia es el CreateDB, y el string de conexión, para tener un usuario de DB para cada Tenant

11. Prueba de Concepto Definimos las siguientes transacciones: Customer, Product, Invoice El precio del producto varía en función del tiempo Creamos una DB singletenant, y otra con varios tenants Cargamos en cada tenant: 2000 clientes, 500 productos, 6000 facturas

12. Prueba de concepto TopCustomers { TopCustomersByYearinput&i = 0 to 3 { &Year = Year(Today()) - &i Year = &Year CustomersorderCustomerName { Customer whereSum(InvoiceTotal, Year(InvoiceDate) = &Year) > 0 { CustomerId CustomerName YearTotal = Sum(InvoiceTotal, Year(InvoiceDate) = &Year) CustomerTotalBought } } } }

13. Prueba de concepto SELECT T1.[CustomerId], T1.[CustomerName], COALESCE( T2.[CustomerTotalBought], 0) AS CustomerTotalBought, COALESCE( COALESCE( T3.[CustomerTotalBought], 0), 0) AS CustomerTotalBought FROM (([Customer] T1 WITH (NOLOCK) LEFT JOIN(SELECT SUM(COALESCE( T5.[InvoiceTotal], 0)) AS CustomerTotalBought, T4.[CustomerId] FROM ([Invoice] T4 WITH (NOLOCK) LEFT JOIN(SELECT SUM(COALESCE( T7.[InvoiceLineTotal], 0)) AS InvoiceTotal, T6.[InvoiceId] FROM ([InvoiceLines] T6 WITH (NOLOCK) INNER JOIN(SELECT T8.[InvoiceLineQuantity] * CAST(COALESCE( T9.[ProductPriceValue], 0) AS decimal( 14, 5)) AS InvoiceLineTotal, T8.[InvoiceId], T8.[ProductId] FROM ([InvoiceLines] T8 WITH (NOLOCK) LEFT JOIN(SELECT T10.[ProductPriceValue], T10.[ProductId], T12.[InvoiceId], T10.[ProductPriceDate], T11.[GXC3] AS GXC3, T13.[InvoiceDate] FROM ((([ProductPrices] T10 WITH (NOLOCK) INNER JOIN [InvoiceLines] T12 WITH (NOLOCK) ON T12.[ProductId] = T10.[ProductId]) LEFT JOIN(SELECT MAX(T14.[ProductPriceDate]) AS GXC3, T14.[ProductId], T15.[InvoiceId] FROM (([ProductPrices] T14 WITH (NOLOCK) INNER JOIN [InvoiceLines] T15 WITH (NOLOCK) ON T15.[ProductId] = T14.[ProductId]) INNER JOIN [Invoice] T16 WITH (NOLOCK) ON T16.[InvoiceId] = T15.[InvoiceId]) WHERE T14.[ProductPriceDate] <= T16.[InvoiceDate] GROUP BY T14.[ProductId], T15.[InvoiceId] ) T11 ON T11.[ProductId] = T10.[ProductId] AND T11.[InvoiceId] = T12.[InvoiceId]) INNER JOIN [Invoice] T13 WITH (NOLOCK) ON T13.[InvoiceId] = T12.[InvoiceId]) WHERE (T10.[ProductPriceDate] = T11.[GXC3]) AND(T10.[ProductPriceDate] <= T13.[InvoiceDate]) ) T9 ON T9.[ProductId] = T8.[ProductId] AND T9.[InvoiceId] = T8.[InvoiceId]) ) T7 ON T7.[InvoiceId] = T6.[InvoiceId] AND T7.[ProductId] = T6.[ProductId]) GROUP BY T6.[InvoiceId] ) T5 ON T5.[InvoiceId] = T4.[InvoiceId]) GROUP BY T4.[CustomerId]) T2 ON T2.[CustomerId] = T1.[CustomerId]) LEFT JOIN(SELECT SUM(COALESCE( T5.[InvoiceTotal], 0)) AS CustomerTotalBought, T4.[CustomerId] FROM ([Invoice] T4 WITH (NOLOCK) LEFT JOIN(SELECT SUM(COALESCE( T7.[InvoiceLineTotal], 0)) AS InvoiceTotal, T6.[InvoiceId] FROM ([InvoiceLines] T6 WITH (NOLOCK) INNER JOIN(SELECT T8.[InvoiceLineQuantity] * CAST(COALESCE( T9.[ProductPriceValue], 0) AS decimal( 14, 5)) AS InvoiceLineTotal, T8.[InvoiceId], T8.[ProductId] FROM ([InvoiceLines] T8 WITH (NOLOCK) LEFT JOIN(SELECT T10.[ProductPriceValue], T10.[ProductId], T12.[InvoiceId], T10.[ProductPriceDate], T11.[GXC3] AS GXC3, T13.[InvoiceDate] FROM ((([ProductPrices] T10 WITH (NOLOCK) INNER JOIN [InvoiceLines] T12 WITH (NOLOCK) ON T12.[ProductId] = T10.[ProductId]) LEFT JOIN(SELECT MAX(T14.[ProductPriceDate]) AS GXC3, T14.[ProductId], T15.[InvoiceId] FROM (([ProductPrices] T14 WITH (NOLOCK) INNER JOIN [InvoiceLines] T15 WITH (NOLOCK) ON T15.[ProductId] = T14.[ProductId]) INNER JOIN [Invoice] T16 WITH (NOLOCK) ON T16.[InvoiceId] = T15.[InvoiceId]) WHERE T14.[ProductPriceDate] <= T16.[InvoiceDate] GROUP BY T14.[ProductId], T15.[InvoiceId] ) T11 ON T11.[ProductId] = T10.[ProductId] AND T11.[InvoiceId] = T12.[InvoiceId]) INNER JOIN [Invoice] T13 WITH (NOLOCK) ON T13.[InvoiceId] = T12.[InvoiceId]) WHERE (T10.[ProductPriceDate] = T11.[GXC3]) AND(T10.[ProductPriceDate] <= T13.[InvoiceDate]) ) T9 ON T9.[ProductId] = T8.[ProductId] AND T9.[InvoiceId] = T8.[InvoiceId]) ) T7 ON T7.[InvoiceId] = T6.[InvoiceId] AND T7.[ProductId] = T6.[ProductId]) GROUP BY T6.[InvoiceId] ) T5 ON T5.[InvoiceId] = T4.[InvoiceId]) WHERE YEAR(T4.[InvoiceDate]) = @YearGROUP BY T4.[CustomerId] ) T3 ON T3.[CustomerId] = T1.[CustomerId]) WHERE COALESCE( COALESCE( T3.[CustomerTotalBought], 0), 0) > 0 ORDER BY T1.[CustomerName]

14. Conclusión Seguimos investigando Eventualmente vamos a tener las 3 Si tienen ideas o experiencia, queremos escucharlas

15. ¡Muchas Gracias! Federico Azzato, GeneXus Development fazzato@artech.com.uy @FedeAzzato