SQL 複製 WHERE StartDate > '20000101' AND EndDate <= '20000630' WHERE ComponentID IN (533, 324, 753) WHERE StartDate IN ('20000404', '20000905') AND EndDate IS NOT NULL 已篩選的索引不適用於 XML 索引和全文檢索索引。 如果是 UNIQUE 索引,只有選取的資料列必須有唯一的索引值。 已篩選的...
Unique and Nonunique Indexes Types of Indexes How the Database Maintains Indexes Index Storage Advantages and Disadvantages of Indexes The absence or presence of an index does not require a change in the wording of any SQL statement. An index is a fast access path to a single row of data....
For more information about SQL Server index types and limitations on indexes applied to tables, see CREATE INDEX (Transact-SQL). Set optional properties, such as FileGroup. Get the Table object that references the SQL Server table you want from the Tables collection of a connected Database ...
also create indexes on computed columns that are defined as method invocations off a user-defined type column, as long as the methods are marked deterministic and do not perform data access operations. For more information about indexing CLR user-defined type columns, seeCLR User-defined Types. ...
To see which indexes the query optimizer uses for a specific query, in SQL Server Management Studio, on the Query menu, select Include Actual Execution Plan. Don't always equate index usage with good performance, and good performance with efficient index use. If using an index always...
PL/SQL Packages and Types Referencefor more information on theDBMS_STATSpackage Noteson Function-based Indexes When you subsequently query a table that uses a function-based index, you must ensure in the query that is not null. However, Oracle Database will use a function-based index in a ...
If no default element namespace is declared, unqualified names of element and types are in no namespace. Only one default namespace can be declared. pattern-expression Pattern-expression is used to identify those nodes in an XML document that are indexed. Pattern-expression cannot be an empty ...
and varbinary(max) data types cannot be specified as index key columns. However, varchar(max), nvarchar(max), varbinary(max), and xml data types can participate in a nonclustered index as nonkey index columns. For more information, see the section 'Index with Included Columns' in this guid...
Variable length data stored in varchar, nvarchar, varbinary, or sql_variant columns that exceed the 8,060 byte row size limit. Pages are of type Text/Image. For more information about page types, seeUnderstanding Pages and Extents. A heap or B-tree can have only one allocation unit of eac...
SQL 複製 WHERE StartDate > '20000101' AND EndDate <= '20000630' WHERE ComponentID IN (533, 324, 753) WHERE StartDate IN ('20000404', '20000905') AND EndDate IS NOT NULL 已篩選的索引不適用於 XML 索引和全文檢索索引。 如果是 UNIQUE 索引,只有選取的資料列必須有唯一的索引值。 已篩選的...