MySQL multilevel comment reply sorting - sql

My current comment reply system:
1
1.1
1.2
1.2.1
10
2
2.1
I can sort the comments from table by their ids (as above) and indent depending on the number of dashes.
The problem is that '10' comes right after '1.2.1'. Is it possible to sort values such as '1.2.1' as a number and not string?
Does any number data type excepts multiple dots or commas?
Thanks in advance!

The common way in materialized path trees is to pad ids to a N-digit number with zeros so it comes 00001 etc
00001
00001.00001
00001.00002
00001.00002.00001
00002
00002.00001
00010

Related

BiqQuery: Remove last N characters

I am trying to remove last 8 characters from a long string but only in case it ends with the 6 character string in the parenthesis (the bolded ones). Does anyone know how to do this in BigQuery?
here are some very random data examples:
01/5/2014 - new planted trees - email - juniper
04/22/2021 - fridge remote‚I want fresh tea (xgssjj)
re- engagement email
5/20 - example reminder (hfgfgh)
repeat customer example #2 (ttrdgd)
Thanks!
Consider below approach
select longString,
trim(regexp_replace(longString, r'\(\w{6}\)$', '')) newString
from your_table
if applied to sample data in your question - output is

SQL different null values in different rows

I have a quick question regarding writing a SQL query to obtain a complete entry from two or more entries where the data is missing in different columns.
This is the example, suppose I have this table:
Client Id | Name | Email
1234 | John | (null)
1244 | (null) | john#example.com
Would it be possible to write a query that would return the following?
Client Id | Name | Email
1234 | John | john#example.com
I am finding this particularly hard because these are 2 entires in the same table.
I apologize if this is trivial, I am still studying SQL and learning, but I wasn't able to come up with a solution for this and I although I've tried looking online I couldn't phrase the question in the proper way, I suppose and I couldn't really find the answer I was after.
Many thanks in advance for the help!
Yes, but actually no.
It is possible to write a query that works with your example data.
But just under the assumption that the first part of the mail is always equal to the name.
SELECT clients.id,clients.name,bclients.email FROM clients
JOIN clients bclients ON upper(clients.name) = upper(substring(bclients.email from 0 for position('#' in bclients.email)));
db<>fiddle
Explanation:
We join the table onto itself, to get the information into one row.
For this we first search for the position of the '#' in the email, get the substring from the start (0) of the string for the amount of characters until we hit the # (result of positon).
To avoid case-problems the name and substring are cast to uppercase for comparsion.
(lowercase would work the same)
The design is flawed
How can a client have multiple ids and different kind of information about the same user at the same time?
I think you want to split the table between clients and users, so that a user can have multiple clients.
I recommend that you read information about database normalization as this provides you with necessary knowledge for successfull database design.

Extracting data from SAS data set based on values with different length

I am looking to automate a process which has a sales dataset and a specific column named SALES CODE which is of 5 letters.
Based on the input given by the user I would like to filter the data but the problem is the user can give multiple sales codes and sometimes the length of codes could be 5,4,3,2 or 1 based on the condition. How will I filter out the required rows based on the above condition?
SALESCODE area value units rep
A10AA KR 100 10 Jay
B10AQ TN 120 12 Jrn
C10AH KR 200 10 Jay
T11TA TR 180 10 Jay
Say if I give the input as A10AA, B10A, T11 I should be able to
Get the sales data with codes A10AA, B10AQ, T11TA. kindly help.
Use the IN operator. Since you want to match values that start with the specified value use the : modifier. Since your values are character values make sure to include quotes.
proc print data=sales_data ;
where salescode in: ("A10AA" "B10A" "T11");
run;
If you want you can use commas between the values in the list, but I find it easier to type spaces instead.

How to sort string data that represents numbers

My client has a set of numeric data stored in a string field in a database. So of course it doesn't sort correctly. These rows sort like this:
105
3
44
When they should sort like this:
3
44
105
This is very much a legacy database and I can't change it at all. I also can't change the software that uses the database. The client doesn't own it or have the source code. It has never worked the way they want. However, there is an unused string field that I could use to sort on (only a small number of fields can be sorted on.)
What I would like to do is take the input data, derive a string from it, and store the new string in the unused field, such that when the data is sorted on this new data, the original data sorts correctly, i.e., numerically.
So, for an overly simplistic example, if the algorithm produced the following new data:
105 -> c
3 -> a
44 -> b
Then when the second column was sorted, the first column would look 'correct'.
The tricky bit is that when new rows are added to the database, they must also sort correctly, without having to regenerate the sort data for all rows. This is the part of the problem that has my brain in a twist. I'm not sure it's actually possible.
You can assume that the number will never be more than 5 'digits'.
I realize this is a total kludge, but since I can't change the system, I have to find a work around, rather than a quality solution. Welcome to the real world.
~~~~~~~~~~~~~~~~~~~~~~ S O L U T I O N ~~~~~~~~~~~~~~~~~~
I don't think this is an uncommon problem, so here are the results of Gordon's solution:
mysql> select * from t order by new;
+------+------------+
| orig | new |
+------+------------+
| 3 | 0000000003 |
| 44 | 0000000044 |
| 105 | 0000000105 |
+------+------------+
In most databases, you can just do:
order by cast(col as int)
This will convert the string representation to a number and use that for ordering. There is no need for an additional column. If you add one, I would recommend adding a numeric column to contain the actual value.
If you really want to store something in the unused field, then you can left pad the number. How to do this depends on the database, but here is one typical method:
update t
set unused = right(concat('0000000000', col), 10);
Not all databases support these two specific functions, but all offer this basic functionality in some method.
Try something like
SELECT column1 FROM table1 ORDER BY LENGTH(column1) ASC, column1 ASC
(Adjust the column and table name for your environment.)
This is a bit of a hack but works as long as the "numbers" in your string column are natural, non-negative numbers only.
If you are looking for a more sophisticated approach or algorithm, try searching for natural sort together with your DBMS.

Jasper / DynamicJasper: How to invert Column Headers

I have a Jasper report with the following output format:
Item | Price | Quantity
----------------------------
1 100 5
2 150 8
3 200 11
How do I make that table to this format:
Item 1 2 3
Price 100 150 200
Quantity 5 8 11
The column headers have now become row headers.
I'm actually using DynamicJasper, but of course, it's still relies on Jasper.
What special setting or property should I set to achieve the format I'm looking for.
Also, what do you call this format? Inverted Headers? Inverted Columns? It's hard to Google this issue since the keywords I'm using doesn't seem to be correct. Google always gives me a different answer.
Please check if Crosstabs serve your purpose
As it was suggested before, either check out crosstab, or you can check their CrosstabBuilder/LayoutManager classes and probably override/extend some to adopt to your needs