Examples For PLSQL Cursors - Explicit, Implicit And Ref Cursors

【Examples For PLSQL Cursors - Explicit, Implicit And Ref Cursors】的更多相关文章

Examples For PLSQL Cursors - Explicit, Implicit And Ref Cursors

A cursor acts logically as a pointer into a result set. You can move the cursor through the result set, processing each row, until you determine you are at the end of the result set. There are three types of syntax associated with cursors: creating t…

C#类型转换运算符之 explicit implicit

类型转换运算符 explicit和implicit用于声明用户定义的类型转换运算符,如果可以确保转换过程不会造成数据丢失,则可使用这两个关键字在用户定义的类型和其他类型之间进行转换. explicit 明确的.明显的称为:显式 implicit 含蓄的.暗含的称为:隐式它们解决什么问题? 考虑下面的需求,Person类有个字段age.我想使用 Person p = (Person) 18 来创建一个age为18的Person对象,怎么办? 更进一步,我想使用Person p = 18 来创…

Oracle PLSQL Demo - 20.弱类型REF游标[没有指定查询类型，也不指定返回类型]

declare Type ref_cur_variable IS REF cursor; cur_variable ref_cur_variable; v_ename ); v_deptno ); v_sal ,); v_sql ) := 'select t.ename, t.deptno, t.sal from scott.emp t'; begin Open cur_variable For v_sql; Loop fetch cur_variable InTo v_ename, v_dep…

Oracle PLSQL Demo - 16.弱类型REF游标[没有指定查询类型，已指定返回类型]

declare Type ref_cur_variable IS REF cursor; cur_variable ref_cur_variable; rec_emp scott.emp%RowType; v_sql ) := 'select * from scott.emp t'; begin Open cur_variable For v_sql; Loop fetch cur_variable InTo rec_emp; Exit When cur_variable%NotFound; d…

On Caching and Evangelizing SQL

http://www.oracle.com/technetwork/issue-archive/2011/11-sep/o51asktom-453438.html Our technologist caches scalar subqueries, votes for SQL, and recommends technology and community. One of the talks I gave recently at the Oracle Benelux User Group (…

C#中的Explicit和Implicit

今天在Review一个老项目的时候,看到一段奇怪的代码. if (dto.Payment == null) continue; var entity = entries.FirstOrDefault(e => e.LedgerEntryID == dto.LedgerEntryID); dto.Payment = entity?.Payment; 其中dto.Payment是一个PaymentDTO类的实例,entity?.Payment是一个Payment类的实例,PaymentDTO类和Pa…

Converting REF CURSOR to PIPE for Performance in PHP OCI8 and PDO_OCI

原文地址:https://blogs.oracle.com/opal/entry/converting_ref_cursor_to_pipe REF CURSORs are common in Oracle's stored procedural language PL/SQL. They let you pass around a pointer to a set of query results. However in PHP, PDO_OCI doesn't yet allow fetch…