To remove the primary key from a table use the following syntax. ALTER TABLE Customer DROP PRIMARY KEYTry it live With this command, the column is no longer used as a primary key. It does not delete the column. Composite KeysA composite key is a primary key which that consists of ...
alter table 表名 字段操作;:修改一张表的字段结构,操作如下: add column 字段名 数据类型:向已有的表结构添加一个字段。 add primary key(字段名):将某个字段声明为主键。 add foreing key 外键字段 表名.字段名:将一个字段设置为另一张表的外键。 add unique 索引名(字段名):为一个字段创建唯一索引。
# 提示在这个过程中需要重启GreatSQL-02节点实例 # 如果无法自动重启,需要手动重启 NOTE: A server restart is expected to happen as part of the clone process. If the server does not support the RESTART command or does not come back after a while, you may need to manually start it back. * ...
SELECT wg.name AS workload_group_name, rp.name AS resource_pool_name, r.command, r.status, d.name AS database_name, COUNT(1) AS request_count, MIN(r.start_time) AS first_request_start_time, MAX(r.start_time) AS last_request_start_time, SUM(CAST(r.total_elapsed_ti...
-a, --auto-generate-sql Generate SQL where not supplied by file or command line. --auto-generate-sql-add-autoincrement Add an AUTO_INCREMENT column to auto-generated tables. --auto-generate-sql-execute-number=# Set this number to generate a set number of queries to run. --auto-generate...
Price =1}).ExecuteCommand(); mysqldb.Queryable<Order>().ToList(); sqlServerdb.Queryable<Order>().ToList(); db.CommitTran(); Feature6 : Singleton Pattern Implement transactions across methods publicstaticSqlSugarScope Db =newSqlSugarScope(newConnectionConfig() ...
SQL Server 使用 Command 從Session 物件建立 IDBCreateCommand::CreateCommand 物件。 如果Remote Query Timeout 伺服器設定選項設定為值 > 0,則 SQL Server 會使用 DBPROP_COMMANDTIMEOUT 將Command 物件上的 ICommandProperties::SetProperties 屬性設定為相同值;必須呼叫 ICommand::SetCommandText,才能將命令...
(connectionString)) { using (SqlCommand cmd = new SqlCommand(commandText, conn)) { cmd.CommandType = commandType; cmd.Parameters.AddRange(parameters); conn.Open(); return cmd.ExecuteScalar(); } } } // Set the connection, command, and then execute the command with query and return the ...
NOTICE: Replica identity is neededforshard table, pleaseaddto this table through"alter table"command. CREATE TABLE 建立两个子表,分别存入“广东”和“北京” postgres=# create table t_list_gd partition of t_native_list(f1 ,f2 , f3,f4) for values in ('广东'); ...
T>(queryText, commandTimeout: 120).ToList(); } } catch (Exception ex) { Console.WriteLine("Failed to execute {0} with error message : {1}, StackTrace: {2}.", queryText, ex.Message, ex.StackTrace); // return empty list return new List<T>(); } } public static bool DoExecute...