EN一般来说，如果在单线程环境下进行字符串操作，并且不需要频繁修改字符串，可以使用String类。如果需要...
col4 varchar(500));因为indexed key size的限制是1700, 所以create index ind_t1 on table1(col1, col2,col3)没有问题,因为col1+col2+col3=1500<1700,但是create index ind_t2 on table1(col1, col2,col3,col4)有问题,因为col1+col2+col3+col4=2000>1700,但是我们可以这样create index ind_...
Transact-SQL 语法约定 语法 适用于 SQL Server、Azure SQL 数据库和 Azure SQL 托管实例的语法 syntaxsql 复制 CREATE [ UNIQUE ] [ CLUSTERED | NONCLUSTERED ] INDEX index_name ON ( column [ ASC | DESC ] [ ,...n ] ) [ INCLUDE ( column_name [ ,...n ] ) ] [ WHERE <filter_predica...
Include nonkey columns in a nonclustered index to avoid exceeding the current index size limitations of a maximum of 32 key columns and a maximum index key size of 1,700 bytes (16 key columns and 900 bytes prior to SQL Server 2016 (13.x)). The Database Engine doesn't consider nonkey...
Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance This article describes how to create indexes on a view. The first index created on a view must be a unique clustered index. After the unique clustered index has been created, you can create more nonclustered indexes. ...
Passwords should always be at least eight characters long, and can't exceed 128 characters. Passwords can include a-z, A-Z, 0-9, and most nonalphanumeric characters. Passwords can't contain single quotes, or the login_name. PASSWORD = hashed_password Applies to the HASHED keyword only. ...
Index independent of a constraint By default, a nonclustered index is created if clustered is not specified. The maximum number of nonclustered indexes that can be created per table is 999. This includes any indexes created by PRIMARY KEY or UNIQUE constraints, but does not include XML indexes...
INCLUDE NULL KEYSEXCLUDE NULL KEYS● Notes: 1In a federated system,table-namemust identify a table in the federated database. It cannot identify a data source table. 2Ifnicknameis specified, the CREATE INDEX statement creates an index specification. In this case, INCLUDE,xml-index-specification...
SQL Server Azure SQL Database Azure SQL Managed Instance This article describes how to create indexes on a view. The first index created on a view must be a unique clustered index. After the unique clustered index has been created, you can create more nonclustered indexes. Creating a unique...
Create a primary XML index Create a secondary XML index See also Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance This article describes how to create primary and secondary XML indexes. Create a primary XML index To create a primary XML index, use the CREATE INDEX (...