hana sql 查询或替换sql hana中的charIndex

Question

i have an requirement to build a SELECT sql hana query in which a column have only single record containg below values in comma separated.

Input :
rowtext,requiredText1,requiredText2,requiredText3,rowtext,rowtext,rowtext,rowtext

Output :
    requiredText1,requiredText2,requiredText3


without using store procedure. 

Table : TestTable
column1                                 column2
pid1                                        rowtext,requiredText1,requiredText2,requiredText3,rowtext,rowtext,rowtext,rowtext
pid2                                        rowtext,requiredText1,requiredText2,requiredText3,rowtext,rowtext
pid3                                        rowtext,requiredText1,requiredText2,requiredText3,rowtext
pid4                                        rowtext,requiredText1,requiredText2,requiredText3,rowtext,rowtext,rowtext 

Answer 1

I understand your question so that you want to remove the rowtext, parts of the input string. An additional difficulty is that there are dangling commas before and after the rowtext that should also be removed.

One way to do this is to use regular expressions similar to this:

with src as (select 'rowtext,requiredText1,requiredText2,requiredText3,rowtext,rowtext,rowtext,rowtext' as INPUT
             from dummy)
select
    replace_regexpr ( ',?rowtext,?' in INPUT WITH '') as output
from src;

OUTPUT                                   
requiredText1,requiredText2,requiredText3

The ,? in the search pattern matches zero or exactly one comma and the rowtext literally matches the search string.