Rules of precedence for operators in an expression Sorting rows using the ORDER BY clause Substitution variables DEFINE and VERIFY commands 1、Restrict 限制(Where-condition)The essential capabilities of SELECT statement are Selection, Projection and Joining. Displaying specific columns from a table is ...
The CREATE INDEX statement creates a partitioning index or a secondary index and an index space at the current server. The columns included in the key of the index are columns of a table at the current server. Invocation for CREATE INDEX This statement can be embedded in an application ...
ORDER BY "column_name" [ASC, DESC]; The [ ] means that the WHERE statement is optional. However, if a WHERE clause exists, it comes before the ORDER BY clause. ASC means that the results will be shown in ascending order, and DESC means that the results will be shown in descending ...
SELECTitem_nameFROMlegacy_productsUNIONSELECTitem_nameFROMnew_products; Each SELECT statement within the UNION must have thesame number of columnswithsimilar data types. The columns in each SELECT statement must be in thesame order. By default, the UNION operator selects onlydistinctvalues. 2.3 Uni...
This SQL tutorial explains how to use the SQL SELECT statement with syntax, examples, and practice exercises. The SQL SELECT statement is used to retrieve records from one or more tables in your SQL database.
The statement cannot be processed. 1 Cannot access the sqllib directory of the instance. 2 The full path name added to the profile filename is too long. 3 Cannot open the profile file. 4 This message is returned with reason code 4 for the following reasons: The specified value for DB...
*/ CREATE INDEX ord_customer_ix_demo ON orders (order_mode) NOSORT NOLOGGING; Creating a Cluster Index: ExampleTo create an index for the personnel cluster, which was created in "Creating a Cluster: Example", issue the following statement:...
ORDERBYCountry, CustomerName; Try it Yourself » Using Both ASC and DESC The following SQL statement selects all customers from the "Customers" table, sorted ascending by the "Country" and descending by the "CustomerName" column: Example ...
Subquery SELECT statements that appear inside an IF statement. The TOP, TABLESAMPLE, HAVING, GROUP BY, ORDER BY, OUTPUT...INTO, or FOR XML clauses of a query. Arguments, either direct or as subexpressions, to OPENROWSET, OPENQUERY, OPENDATASOURCE, OPENXML, or any FULLTEXT operator. The pat...
CLR user-defined types are created with the CREATE TYPE statement before they can be used in a table definition. To create a column on CLR user-defined type, REFERENCES permission is required on the type. If type_schema_name isn't specified, the SQL Server Database Engine references type_...