SQL Server (and Npgsql) can only cache a certain number of SQLs at some point, they have to get rid of old entries to avoid using too much memory. In addition, EF itself has an internal SQL cache for its queries, and this SQL variance makes caching impossible, leading to further EF overhead for each and every query.īut crucially, the negative performance impact of constantly varying SQLs goes beyond this particular query. This is vital for good performance: SQL Server caches SQL, performing expensive query planning only the first time a particular SQL is seen (a similar SQL cache is implemented in the database driver for PostgreSQL). This has the unfortunate consequence that the SQL produced by EF varies for different array contents – a pretty abnormal situation! Usually, when you run the same LINQ query over and over again – changing only parameter values – EF sends the exact same SQL to the database. NET variables in EF LINQ queries usually become SQL parameters, in this particular case the variable has disappeared, and its contents have been inserted directly into the SQL. īut wait, this looks suspiciously familiar – it’s the inline collection translation we saw above! And indeed, since we couldn’t parameterize the array, we simply embedded its values – as constants – into the SQL query. Up to now, all versions of EF have provided the following translation: SELECT. But what can we do for other databases, where this does not exist? Leveraging this, we pass the array of blog names as a SQL parameter directly to ANY – that’s – and get the perfect translation. WHERE b."Name" = ANY is very similar to the inline collection translation above with IN, but uses the PostgreSQL-specific ANY construct, which can accept an array type. Where(b => new (DbType = Object)], CommandType='Text', CommandTimeout='30'] You could use the following LINQ query to do so: var blogs = await context.Blogs Starting from something simple, imagine you have a bunch of Blogs, and want to query out two Blogs whose names you know. Let’s examine such a case, which also happens to be related to a highly-voted EF performance issue. ![]() ![]() In EF’s quest to translate more and more LINQ queries to SQL, we sometimes encounter odd and problematic corner cases. Let’s dive in! Translating LINQ Contains with an inline collection The fourth preview version of EF Core 8.0 preview4 includes some exciting new capabilities in query translation, as well as an important performance optimization. NET 8 as a long-term support (LTS) release. NET 8 as we near release.ĮF8 will align with. NET 6, and can therefore be used with either. Migration also supports migrating from earlier versions of MySQL to the latest releases.The fourth preview of Entity Framework Core (EF Core) 8 is available on NuGet today! Basic informationĮF Core 8, or just EF8, is the successor to EF Core 7, and is scheduled for release in November 2023, at the same time as. Developers and DBAs can quickly and easily convert existing applications to run on MySQL both on Windows and other platforms. MySQL Workbench now provides a complete, easy to use solution for migrating Microsoft SQL Server, Microsoft Access, Sybase ASE, PostreSQL, and other RDBMS tables, objects and data to MySQL. Plus, with 1 click, developers can see where to optimize their query with the improved and easy to use Visual Explain Plan. Performance Reports provide easy identification and access to IO hotspots, high cost SQL statements, and more. DBAs can quickly view key performance indicators using the Performance Dashboard. MySQL Workbench provides a suite of tools to improve the performance of MySQL applications. Learn more » Visual Performance Dashboard Developers and DBAs can use the visual tools for configuring servers, administering users, performing backup and recovery, inspecting audit data, and viewing database health. ![]() MySQL Workbench provides a visual console to easily administer MySQL environments and gain better visibility into databases. The Object Browser provides instant access to database schema and objects. The Database Connections Panel enables developers to easily manage standard database connections, including MySQL Fabric. The SQL Editor provides color syntax highlighting, auto-complete, reuse of SQL snippets, and execution history of SQL. MySQL Workbench delivers visual tools for creating, executing, and optimizing SQL queries. It includes everything a data modeler needs for creating complex ER models, forward and reverse engineering, and also delivers key features for performing difficult change management and documentation tasks that normally require much time and effort. MySQL Workbench enables a DBA, developer, or data architect to visually design, model, generate, and manage databases.
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