In this tutorial, you will learn how to use the Oracle function-based index to speed up queries that consist of functions.
Function-based index 可以很巧妙地帮助我们实现“不一般”的unique index, 但是如果没有注意function-based index对于该index对应的function的要求,很有可能会触发ORA-01802这个错误。 本文尝试去阐述这个错误是如何触发的,以及如果去解决。 OK, let’s get down to business. 记得Tom大叔的力作《Oracle编程艺术》中提...
Because 'DECODE(status, 'C', null, status)' has been set in the Function-Based Index 'T1_STATUS_FN', you, certainly, create the virtual column 'virtual_status' with 'DECODE(status, 'C', null, status)' and Oracle will show this error: 'ORA-54015: Duplicate column expression was speci...
You must specify this keyword if you intend to call the function in the expression of a function-based index or from the query of a materialized view that is markedREFRESHFASTorENABLEQUERYREWRITE. When Oracle Database encounters a deterministic function in one of these contexts, it attempts to ...
A nonunique index can be used to enforce a primary key or unique constraint. In Oracle8i indexes can be rebuilt without locking the table. The DROP COLUMN option of the ALTER TABLE command is restartable. The MOVE option of the ALTER TABLE command retains the constraints of the table. Data...
链接:https://www.eygle.com/archives/2006/01/create_function_based_index.html 留言版上的第2330号问题是: 在oralce中给自建函数创建索引,结果不成功。 source:Create Index IDX_T_SP_TWOTYPESTAT_0_f On T_SP_TWOTYPESTAT_0(f_dateadd(yearmonth,12,2)); ...
oracle 函数Function 基本使用 函数Function |-概念:与存储过程类似,遵循相同的规则,只能传递IN类型参数,不能使用OUT类型参数,其主要特征是必须有返回值; |-函数和存储过程的异同: |-标识符不同,函数-Function,存储过程-procedure; |-函数中一般不用传递变量,除非作为调试使用。使用函数名直接返回函数值;...
Oracle Database - Enterprise Edition - Version 12.2.0.1 and later: After Partitioning Table Using 'ALTER TABLE MODIFY PARTITION' Statement, FUNCTION-BASED Index Gets
I understand that there are no function based indexes but there are alternatives like generated columns. But, I wanted to check if there is a possibility to add an index on (col1 + offset) without adding a new column ?? Thanks in advance ...
Function-Based Index on numeric Column 3369 Nicola Pascelupo March 25, 2011 07:28AM Re: Function-Based Index on numeric Column; num LIKE '123%' 1140 Rick James March 26, 2011 10:34AM Sorry, you can't reply to this topic. It has been closed. ...