Data cleansing Note: determines whether it is a date function or a note date

Data cleansing Note: determines whether it is a date function or a note date

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Deep Blue blog: http://blog.csdn.net/huangyanlong/article/details/46507701

 

Background]

When extracting data from a certain date, it is found that a large amount of non-date data exists, and spam data (non-date data) needs to be cleaned ).

 

[Solution]

Write a simple function to determine whether the data is a date, extract the data as a "date", and assign the date to it. For non-date data, assign null processing.

Refer to the following:

/*************************************** *************************

* Name: estimate_date

* Function: determines whether a string can be converted to a normal date. If it cannot be null

* Input: isdate

* Output: isdate

* Author: Deep Blue

* CreateDate: 20150614

* UpdateDate: 20150614

**************************************** ************************/

create or replace function estimate_date (isdate varchar2) return varchar2 isd date;begin  d:=to_date (nvl (isdate, ' '), 'yyyy-mm-dd hh24:mi:ss');  return isdate;  exception  when others then  return '';end;

 

[Experiment]

select estimate_date('2014/05/06 23:01:18') from dual;

select estimate_date('aaaaaaa') from dual;

Small knowledge, easy to remember.

 

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Original works, from the blog of "Deep Blue". You are welcome to reprint them. Please indicate the source (Http://blog.csdn.net/huangyanlong).

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Original works, from the blog of "Deep Blue". You are welcome to reprint them. Please indicate the source (Http://blog.csdn.net/huangyanlong).

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