vitallooki.blogg.se - Mysql optimizer hint

You will be responsible for generated SQL as LinqToDB will generate SQL based on what you pass as parameters. The extension methods above are common and can be used to generate SQL for all database providers. OPTION (RECOMPILE, FAST 10, MAX_GRANT_PERCENT=25) WITH (SPATIAL_WINDOW_MAX_CELLS=10, Index(IX_ChildIndex)) JoinHint() on c.ParentID equals p.ParentID IndexHint(, "IX_ChildIndex")įrom t in db.Parent.With() `Child` `c_1` USE KEY FOR ORDER BY(IX_ChildIndex, IX_ChildIndex2) SELECT /*+ PK_Parent) SET_VAR(sort_buffer_size=16M) */

QueryHint(, Sql.TableSpec("Pr"), Sql.TableSpec("Ch")) IndexHint(, "IX_ChildIndex", "IX_ChildIndex2") To create these names, use the following methods: AsSubQuery("qb_name") Oracle and MySql table-level, index-level, and subquery optimizer hints permit specific query blocks to be named as part of their argument syntax. The following methods can be used as hint parameters to generate table references: Method

The TableID method assigns provided identifier to a table and this ID can be used later to generate references to the table. LinqToDB automatically generates table and subquery aliases, so the idea to use generated names for hints is definitely not the best. Some hints require references to table specifications or aliases. The TableHint extension generates Oracle hints, whereas this extension supports SqlServer hint style. MySql supports both hint styles: Oracle Optimizer Hints and SqlServer Table Hints. It is supported by the same database providers as TableHint. This method applies provided hint to all the tables in scope of this method.

This type of extension should not generate SQL and can be used to implement path through methods such as AsSqlServer() that converts IQueryable sequence to ISqlServerSpecificQueryable. The QueryExtensionScope enumeration defines a scope where this extension is applied to. Query Extensions are designed to extend SQL on clause and statement level such as table, join, query hints, etc. LinqToDB contains different mechanisms to extend and customize generated SQL.