You cannot 'see' the hash table anywhere, it is an internal data structure that lives in your session memory for the duration of the query. Once the query is finished - it goes away. It is a cache associated with your query - nothing more, nothing less. You can "see" it in action ...
在这里结合自己的理解,重新演示一下,下面测试环境为Oracle 11g,关于Hash Table,估计有些人会比较懵,借用Tom大神的述说: You cannot 'see' the hash table anywhere, it is an internal data structure that lives in your session memory for the duration of the query. Once the query is finished - it goe...
ExecuteReader System.Data.DataSet ExecuteReader(string Query) ExecuteScalar string ExecuteScalar(string Query)As an example, the signature for the generic operation methods is shown in the following code snippet.Copy public partial class GenericOperation_Clien...
<ExecuteReader xmlns="http://schemas.microsoft.com/OracleEBS/2008/05/GenericOperation/"> <Query>SELECT * FROM ACCOUNTACTIVITY</Query> </ExecuteReader> 如需使用 Oracle E-Business 配接器叫用 ExecuteReader 作業的要求訊息架構的詳細資訊,請參閱 ExecuteReader...
ScalarSubquery You can place aScalarSubqueryanywhere anExpressionis permitted. AScalarSubqueryturns aSelectExpressionresult into a scalar value because it returns only a single row and column value. The query must evaluate to a single row with a single column....
XmlCommandTypeプロパティの値が次のいずれかに設定されている場合、ExecuteScalarメソッドがInvalidOperationExceptionをスローします。OracleXmlCommandType値:Insert、Update、Delete、Query。 例 // C# using System; using System.Data; using Oracle.DataAccess.Client; class ExecuteScalarSample { static void ...
as… 是固定的语法格式 打印traceback信息 finally 后的代码不管是否抛出异常都会执行 except 的原理 ...
The transformed query may qualify for other transformations or optimizations, or may otherwise be executed or optimized differently from the initial query.doi:US8521723 B1Rafi AhmedUSUS8521723 * Jul 18, 2012 Aug 27, 2013 Oracle International Corporation Transforming correlated scalar subqueries...
public void CreateOracleCommand(string myScalarQuery, OracleConnection connection) { OracleCommand command = new OracleCommand(myScalarQuery, connection); command.Connection.Open(); command.ExecuteScalar(); connection.Close(); } Comentarios Use el ExecuteScalar método para recuperar un valor único ...
SQL SERVER中的用户定义函数(User Defined Functions 简称UDF)分为标量函数(Scalar-Valued Function)和表值函数(Table-Valued Function)。其中表值函数又分为Inline table-valued functions和Multistatement table-valued functions。 用户定义函数(UDF)在 SQL Server 中发挥重要的作用。用户定义函数可以用于执行复杂的逻辑...