SQL query to fetch rows based on a column - sql

I have a table Employee as below. The Change column contains names of columns whose values are modified through my application. Data in this column is separated by comma. I need to query this table in such a way that the result will have one change per row. ie split the data in the Change column by comma and fetch the corresponding row. I don't have an idea where to start ! Please help.

Let's see, you could use Oracle's regexp_substr function:
select distinct Id, Name, Address, trim(regexp_substr(Change,'[^,]+', 1, level))
from Employee
connect by regexp_substr(Change, '[^,]+', 1, level) is not null;
This should work for any number of comma-separated values in your Change column.
See doc on the rexexp_substr function here: https://docs.oracle.com/cd/B12037_01/server.101/b10759/functions116.htm

here i have tried with the use of regexp_substr included multiset level
with temp as
(
select id, name, address, change from testemp
)
select id,name,address,trim(regexp_substr(change, '[^,]+', 1, levels.column_value)) change
from temp t,
table(cast(multiset(select level from dual
connect by level <= length (regexp_replace(change, '[^,]+')) + 1)
as sys.OdciNumberList)) levels;

Related

Search and extract data from SQL column having some delimiter

I have column in table having data in below format:
(DeliveryMethod+NON;Installation_Method+NoInstallation;Services_Reference_ID+100118547,44444,33333;Service_ID+2222)
(key+value;key+value;key+value;key+value;key+value;key+value;key+value;)
I want to search and extract a particular "value" from this column based on specific "key" and "key+value" can be on any position, how to do this using a SQL query?
Here's one way to approach it in Oracle as I answered in this post: Oracle 11gR2: split string with multiple delimiters(add). Hopefully you can apply the logic to your RDBMS. Note that this answer doesn't just get the value from the string, but attempts to parse the string and return values so they can be processed like rows in a query's result set. This may be overkill for your scenario. At any rate, it's just one way to look at it.
-- Original data with multiple delimiters and a NULL element for testing.
with orig_data(str) as (
select 'DeliveryMethod+NON;Installation_Method+NoInstallation;;Services_Reference_ID+100118547,44444,33333;Service_ID+2222' from dual
),
--Split on first delimiter (semi-colon)
Parsed_data(rec) as (
select regexp_substr(str, '(.*?)(;|$)', 1, LEVEL, NULL, 1)
from orig_data
CONNECT BY LEVEL <= REGEXP_COUNT(str, ';') + 1
)
-- For testing-shows records based on 1st level delimiter
--select rec from parsed_data;
-- Split the record into columns
select regexp_replace(rec, '^(.*)\+.*', '\1') col1,
regexp_replace(rec, '^.*\+(.*)', '\1') col2
from Parsed_data;
Result:
To specifically answer your question, in order to get a value based on a key, change the last query to this in order to get the value where the key is 'Service_ID':
select value
from (
select regexp_replace(rec, '^(.*)\+.*', '\1') key,
regexp_replace(rec, '^.*\+(.*)', '\1') value
from Parsed_data )
where key = 'Service_ID';
Result:
Or to just extract it out of the string using a regular expression:
with orig_data(str) as (
select 'Service_ID+2222;DeliveryMethod+NON;Installation_Method+NoInstallation;;Services_Reference_ID+100118547,44444,33333' from dual
)
select regexp_substr(str, '(.*?)Service_ID\+(.+?)(;|$)', 1, 1, NULL, 2) value
from orig_data;

concat two strings totalling >4000 characters

I am trying to combine two columns from one table (A) into on column in a second table (B). The column in table B is set as CLOB to hold the large amount of data, however when I run the script I get a message that the result of my string concatenation is too long.
INSERT INTO berkshire.tim_rebuttal_prod(
,INVEST_OR_UWG
)
SELECT
,(INVEST_OR_UWG || INVEST_OR_UWG2)
FROM berkshire.stage_rebuttal
select rtrim(xmlagg(xmlelement(e,id,',').extract('//text()') order by id).GetClobVal(),',')
from (select level as id from dual connect by level < 1050)

Oracle- create a temporary resultset for use in a query

How do I create a temporary result set for use in an SQL without creating a table and inserting the data?
Example: I have a list of, say 10 codes for example. I want to put this into a query, and then query the database to see which codes in this temporary list do not exist in a table.
If it was already in a table, I could do something like:
SELECT
ITEM_CODE
FROM
TEMP_ITEMS
MINUS
SELECT
ITEM_CODE
FROM
M_ITEMS
Is their a way without using PL/SQL, and pure SQL to create a temporary rowset before querying?
Please don't answer with something like:
SELECT 1 FROM DUAL
UNION ALL
SELECT 2 FROM DUAL
I am sort of thinking of something where I can provide my codes in an IN statement, and it turns that into rows for use in a later query.
Edit: so everyone knows my objective here, basically I sometimes get a list of product codes that I need to find which ones in the list are not setup in our system. I want a quick way to throw this into an SQL statement so I can see which ones are not in the system (rather than importing data etc). I usually put these into excel, then do a formula such as :
="'"&A1&"',"
So that I can create my comma separated list.
If you are using oracle 11g you can do this
with t as
(
select (column_value).getnumberval() Codes from xmltable('1,2,3,4,5')
)
SELECT * FROM t
WHERE NOT EXISTS (SELECT 1 FROM M_ITEMS M WHERE codes = M.ITEM_CODE);
or
with t as
(
select (column_value).getstringval() Codes from xmltable('"A","B","C"')
)
SELECT * FROM t
WHERE NOT EXISTS (SELECT 1 FROM M_ITEMS M WHERE codes = M.ITEM_CODE);
I would go with:
with t as (
select 1 as val from dual union all
select 2 as val from dual
)
select . . .
And then use "t" or whatever you call it, in the subsequent query block.
I'm not sure what the objection is to using the select method . . . just pop the values you want in a column in Excel and produce the code for each value by copying down the formula. Then paste the results back into your query interface.
If you want to use a temporary table, you can use the values clause. Alternatively, you can use string functions if you only want IN functionality. Put the values in a comma separated list and check to see if it matches a particular value:
where ','||<list>||',' like '%,'||col||',%'
This one is interesting because it's not a union and fit in a single select. You have to enter the string with delimiters ('a/b/c/def') two times though:
SELECT regexp_substr('a/b/c/def', '[^/]+', 1, ROWNUM) var,
regexp_substr('2/432/sd/fsd', '[^/]+', 1, ROWNUM) var2
FROM dual
CONNECT BY LEVEL <= length(regexp_replace('a/b/c/def', '[^/]', '')) + 1;
var var2
=== ====
a 2
b 432
c sd
def fsd
Note: Credits go to : https://stackoverflow.com/a/1381495/463056
So using the with clause it would give someting like :
with tempo as (
SELECT regexp_substr('a/b/c/def', '[^/]+', 1, ROWNUM) var,
regexp_substr('2/432/sd/fsd', '[^/]+', 1, ROWNUM) var2
FROM dual
CONNECT BY LEVEL <= length(regexp_replace('a/b/c/def', '[^/]', '')) + 1
)
select ...
or you can use it in a from clause :
select ...
from (
SELECT regexp_substr('a/b/c/def', '[^/]+', 1, ROWNUM) var,
regexp_substr('2/432/sd/fsd', '[^/]+', 1, ROWNUM) var2
FROM dual
CONNECT BY LEVEL <= length(regexp_replace('a/b/c/def', '[^/]', '')) + 1
) tempo
There are two approaches I would lean towards:
1. Global Temporary Table
Although you say you don't want to create a table, it depends on why you don't want a table. If you choose to create a Global Temporary table, the rows are only visible to the session that inserted them, so it's like having a private in-memory table but gives you all the benefits of a real table - i.e. being able to query and join to it.
2. Pipelined function
You can create a function that returns the results in a form that can be queried using the TABLE() operator. More info here: http://www.oracle-base.com/articles/misc/pipelined-table-functions.php
It's a bit hokey-looking. But you can parse a string into separate rows using regular expressions assuming you are using 10g or later. For example
SQL> ed
Wrote file afiedt.buf
1 SELECT REGEXP_SUBSTR('a,b,c,def,g', '[^ |,]+', 1, LEVEL) parsed_str
2 FROM dual
3* CONNECT BY LEVEL <= REGEXP_COUNT('a,b,c,def,g', '[^ |,]+')
SQL> /
PARSED_STR
--------------------------------------------
a
b
c
def
g
Personally, I would find a pipelined table function or a PL/SQL block that generates a collection easier to understand, but if you have to do it in SQL you can.
Based on your edit, if you are getting a list of product codes that is already in some sort of file, it would seem to make more sense to use an external table to expose the file as a table or to use SQL*Loader to load the data into a table (temporary or permanent) that you can query. Barring either of those options, if you really want to manipulate the list in Excel first, it would make more sense to generate an IN list in Excel and just copy and past that into your query. Generating a comma-separated list of codes in Excel only to parse that list into it's constituent elements in SQL seems like way too many steps.

dynamic number of where condition in oracle sql

I need to write a sql for a prompt in a reporting tool. I get the list of multiple values in a variable separated by '-' and the number of such values can vary.(eg1."abc-def" eg2."abc-def-xyz").
Now I need to write sql in oracle of this form(logically)
select something
from somewhere
where someColumn in 'abc' -- use substr to extract abc
or someColumn in 'def' -- use substr to extract def
or ...till we don't find '-'.
I can't use plsql for the query. Either I may not be knowing to use the variable in which I select into in plsql or may be the reporting tool doesn't support that.
Thanks in advance.
Try
select something
from somewhere
where someColumn in (select regexp_substr('abc-def-xyz','[^-]+', 1, level) from dual
connect by regexp_substr('abc-def-xyz', '[^-]+', 1, level) is not null);
To generalize (considering your fields are separated by "-")
select something
from somewhere
where someColumn in (select regexp_substr(variable,'[^-]+', 1, level) from dual
connect by regexp_substr(variable, '[^-]+', 1, level) is not null);
Basically the output of the subquery is shown below -
SQL> select regexp_substr('abc-def-xyz','[^-]+', 1, level) value from dual
connect by regexp_substr('abc-def-xyz', '[^-]+', 1, level) is not null;
VALUE
--------------------------------
abc
def
xyz
First split the string into its parts using Oracle's regexp_substr() function. See regexp_substr function (If you can access the original that generates the string, just use that.)
Second, put this in a temp table and then just have:
select something
from somewhere
where someColumn in (select parts from tmpTable)
select something
from somewhere
where INSTR('-'||'abc-def-ghi'||'-', '-'||someColumn||'-') > 0;
If you just want a list of results that contain a '-', you could just do something like
SELECT SOMETHING FROM SOMEWHERE WHERE SOMECOLUMN LIKE ('%-%');

Oracle Select numbers from an IN clause

I'm looking for the best way to select numbers directly from an in clause.
Basically like:
SELECT * FROM (2,6,1,8);
That doesn't work. I can do it this way:
SELECT Lv FROM ( SELECT Level LV
FROM DUAL
CONNECT BY Level < 20)
WHERE Lv IN (2,6,1,8);
But that seems to be a bit clunky. Is there a more elegant way?
You can do
select column_value from table(sys.dbms_debug_vc2coll(1,2,3,4,5));
but that actually returns a varchar2. You can create your own TYPE and use that
create type tab_num is table of number;
/
select column_value from table(tab_num(1,2,3,4,5));
It's also worth looking at the MODEL clause. It looks complicated, but it is very good at generating data
SELECT x from dual
MODEL DIMENSION BY (1 AS z) MEASURES (1 x)
RULES ITERATE (7) (x[ITERATION_NUMBER]=ITERATION_NUMBER+1)
It's more elegant if you materialize an auxiliary numbers table:
SELECT num FROM numbers WHERE num IN (2,6,1,8);
And this is also useful when combined with another table.
For instance, I've had a case where I needed to populate large configuration tables with changes from piecewise results:
Big SP or Excel sheet or report identifies missing cost centers in config gives a large set of results which need to be inserted with varying data in some groups.
Paste partial results into a individual comma separated lists:
INSERT INTO {stuff}
SELECT {stuff}, 130 as line_item
FROM numbers
WHERE numbers.num IN ({pasted a section of results})
INSERT INTO {stuff}
SELECT {stuff}, 135 as line_item
FROM numbers
WHERE numbers.num IN ({pasted another section of results})
If you don't explicitly need the IN clause, you could use UNION:
select 2 from dual
union
select 6 from dual
union
select 1 from dual
union
select 8 from dual
There is a more elegant variant to INSERT multiple rows into a table:
INSERT ALL
INTO table (col) VALUES ('a')
INTO table (col) VALUES ('b')
INTO table (col) VALUES ('c')
SELECT * FROM dual;
But I don't know a way to do that for a SELECT.