This is done in PL/SQL, so surround it with "begin" and "end", or use "exec" if you are in SQL*Plus. Also, in order to create preferences, the issuing owner must have the ctxapp role. Once the preference is created, we can customize it using set_attribute: For our example, le...
7-6 Using an Oracle ASM File Name in a SQL Statement ... 7-9 Adding an Alias Name for an Oracle ASM Filename ... 7-10 Example: Renaming an Alias Name for an Oracle ASM Filename ... 7-10 Dropping an Alias Name for an Oracle ASM Filename......
USER_NAME,ADDRESSFROMUSER_FILESWHERETO_NUMBER(USER_NO)=109204421;--因为内部发生的类型转换,这个索引将不会被使用,所以正确的写法应该是:SELECTUSER_NO,USER_NAME,ADDRESSFROMUSER_FILESWHEREUSER_NO='109204421';--但是,在下面的SQL语句中,Oracle隐式地将字符串“...
PL/SQL procedure successfully completed. SCOTT@test01p> exec test_tab_proc1(3, 100); --- Index: name3 like 20211123182827.ONE\_PART.207 --- Total Elapsed MS = 70, Total CR gets= 303, Per Exec MS = .7, Per Exec CR gets = 3 PL/SQL procedure successfully completed. SCOTT@test01p...
In the SQL statement field, enter an appropriate SQL statement. Sample SQL Usergroup Select Statement select EMPLOYEE_ID from FND_USER where EMPLOYEE_ID > 0 This select statement retrieves all employee IDs greater than zero (i.e., all employees) from the fnd_user table. Note: Usergroup sel...
with Database Views Use Data Pump Trace Use SQL Trace Improve Performance with Parallelism and Statistics Use Parallelism Specify wildcards to create multiple Dumpfiles Gather Statistics before and after Data Pump Operations Set Resources Utilization Appropriately Network Mode Import Use Securefile Lobs ...
WHERE子句中, 如果索引列所对应的值的第一个字符由通配符(WILDCARD)开始, 索引将不被采用. SELECT LOADING FROM LOADING WHERE MANAGER LIKE ‘%HANMAN’; 在这种情况下,ORACLE将使用全表扫描. 三.SQL调优的本质就是调整执行计划。 在好多情况下,oracle自动选择的执行计划并不是最优的,这时需要我们人工去干预。(...
define/def:Define variable with initial value, can be used in either SQL bindings or text substitution in command or script file variable/var:Define variable and its data type without value assignment, can be used as the output binding parameter of the SQL statement, mainly used in customized ...
2.2 Native Compilation: The optimal strategy of supporting XMLQuery() and XMLTable, is to rewrite the embedded XQuery, which is a static string, into SQL with XML extension operators so that the entire SQL statement that includes the XMLQuery() functions and XMLTable can be optimized as a ...
直方图是一种按数据出现的频率来进行分类存储的方法.在oracle中直方图是用来描述表中列数据的分布情况.每一个sql在被执行前都要经过优化这一步骤那么在优化器给出一个最优执行计划之优化器应该要知道sql语句中所引用的底层对象的详细信息. 直方图描述的对象包括列中不同值的数量和它们出现的频率.现在存储每一个不同...