Best Practices
- Single SubmitChanges Call: Aim to have one call to
SubmitChanges
to ensure all database operations are performed in a single transaction. - Explicit Column Selection: Specify the column names explicitly to improve performance by reducing data flow.
var result = from t in db.Countries
select new { Name = t.Name, ID = t.CountryID };
- Delay Loading: Set
Delay Loaded
property tofalse
for columns with large data to load them only when necessary. - Use Stored Procedures for Complex Queries: For complex queries, use stored procedures to avoid performance issues with LINQ queries.
- Deferred Execution: Understand that LINQ executes queries when you start iterating over the results, keeping the connection open during this time.
- Immediate Execution: Use
.ToList()
or.ToArray()
to execute queries immediately and store results in memory for lengthy operations.
var data = query.ToList();
- Class Design: Avoid dumping all database tables and stored procedures into a single class. Separate read-only tables and log tables to optimize memory use.
- Multiple Data Contexts: Create separate data context classes for read-only and transactional data. Disable
ObjectTrackingEnabled
for read-only data contexts to improve performance.
DataClasses1DataContext dataContext = new DataClasses1DataContext();
dataContext.ObjectTrackingEnabled = false;
- Disable Optimistic Concurrency: Turn off optimistic concurrency if the application logic ensures the last update wins.
[Column(Storage="_Name", DbType="NVarChar(50) NOT NULL", CanBeNull=false, UpdateCheck=UpdateCheck.Never)]
public string Name { /* implementation */ }
- Monitor Generated Queries: Regularly monitor the queries generated by LINQ to optimize performance and understand query behavior better.
- Compiled Queries: Use
CompiledQuery.Compile
for frequently executed queries to improve performance.
var compiledQuery = CompiledQuery.Compile((DataContext db, int id) => db.Table.FirstOrDefault(t => t.Id == id));
- DataLoadOptions: Use
DataLoadOptions
to prefetch related data and reduce database calls.
DataLoadOptions options = new DataLoadOptions();
options.LoadWith<Student>(s => s.Subject);
context.LoadOptions = options;
- AssociateWith for Filtering: Use
DataLoadOptions.AssociateWith
to filter related data.
DataLoadOptions options = new DataLoadOptions();
options.AssociateWith<Student>(s => s.Subject.Where(sb => sb.Id == 3));
- Paging with Take and Skip: Use
Take()
andSkip()
methods to implement paging and fetch only the required data.
var pagedData = db.Table.Skip(pageIndex * pageSize).Take(pageSize).ToList();
These practices aim to enhance the performance and efficiency of applications using LINQ to SQL. Regular monitoring and optimization are key to maintaining optimal performance.