select@@version;#查询数据库的版本select@@servername;#查询服务名selecthost_name();#查询主机名,如果是用navicat远程连接的话,主机名是本地的名字selectdb_name();#查询当前数据库名selectdb_name(1);#查询第一个数据库名selectdb_name(2);#查询第二个数据库名selectuser;#查询当前数据库的拥有者,结果为 ...
'rows-per-second'='1','fields.show_params.length'='3','fields.log_id.min'='1','fields.log_id.max'='10');CREATETABLEclick_log_table(log_idBIGINT,click_paramsSTRING)WITH('connector'='datagen','rows-per-second'='1','fields.click_params.length'='3','fields.log_id.min'='1','...
SQL Server表的设计(建表) 知识部分 1、SQLServer数据类型·数据类型是数据的一种属性,用来定义数据是时间、数字、字符串(文字、字母)等·SQLServer提供系统数据类型集,该类型集定义了可以与SQLServer一起使用的所有数据类型...image:大约可存储20亿个二进制数据 2、默认值在插入数据是如果对一行的某一列没有键入...
SQL STRING_AGG function is supported by SQL Server version 2017 and higher. STRING_AGG is a built-in string function used to concatenate multiple rows of data into a single string. This function takes all expressions from rows, convert into string type, and concatenates them into a single str...
The ROWGUIDCOL property doesn't enforce uniqueness of the values stored in the column. It also doesn't automatically generate values for new rows inserted into the table. To generate unique values for each column, use the NEWID function on INSERT statements. A default value can be specified; ...
STRING_AGGis an aggregate function that takes all expressions from rows and concatenates them into a single string. Expression values are implicitly converted to string types and then concatenated. The implicit conversion to strings follows the existing rules for data type conversions. For more informa...
SqlConnection connection sql server 连接对象 IEnumerable<T> source 需要批量插入的数据源 string tableName = null 插入表名称【为NULL默认为实体名称】 int bulkCopyTimeout = 30 批量插入超时时间 int batchSize = 0 写入数据库一批数量【如果为0代表全部一次性插入】最合适数量【这取决于您的环境,尤其是行数...
nohup /export/server/hive/bin/hive --service hiveserver2 2>&1 > /tmp/hive-hiveserver2.log &
以下示例从 SQL ServerCustomers数据库本地实例中的Northwind表以及存储在同一计算机上的 AccessOrders数据库中的Northwind表中选择所有数据。 备注 此示例假定已经安装了 Access。 若要运行此示例,必须安装Northwind数据库。 SQL USENorthwind; GOSELECTc.*, o.*FROMNorthwind.dbo.CustomersAScINNERJOINOPENROWSET('Microsof...
('string') example INSERT INTO dbo.EmployeeSales EXECUTE (' SELECT ''EXEC STRING'', sp.BusinessEntityID, c.LastName, sp.SalesYTD FROM Sales.SalesPerson AS sp INNER JOIN Person.Person AS c ON sp.BusinessEntityID = c.BusinessEntityID WHERE sp.BusinessEntityID LIKE ''2%'' ORDER BY sp....