I am working in a small personal project about capital expenses. There is one part I can't figure it out.
The tables i have are the following:
capex_form
capex_cashflow
When I create a capex_form I am able to request money and divide this money however I want in 13 months including this month (to show how I I will pay it in the next year). this will reflect in capex_cashflow who has 13 columns with either an amount or 0.
The problem comes here:
I need to be able to add many descriptions for each payment. For example:
in July 2019 I will spend 200 ( this is done), I need to enter a breakdown of this 200 dollars and a description. 50 dollars on one thing and 150 on another thing.
I added 3 columns per month which works, But then it will only let me add one description per month.
I was thinking I might be able to create another table for description, but how this is going to related to a specific column(month). As far as my brain gives, you relate one table with another table not column.
I also was thinking to create 13 tables for 13 months, but I think there should be something I am missing to avoid to create 13 unnecessary tables.
I appreciate any kind of help or guidance
This is pretty straightforward and a common thing.
Put an index column in the "header" table. The header table is a summary of the information, so in your case may you create a table that just takes the capex_income.
CAPEX_FORM
Capex_id
Capex_Amount
Then create a payment table, the payment table can have a month column (only 1) and a capex_Id column, along with a description or whatever else you need
CAPEX_PAYMENT
Capex_payment_id
Capex_id
Payment_Amount
Month (1-13)
Description
Now because you have the Capex_id in this table, it will be related to the CAPEX table and you will be able to query all the payments that are associated like so
select payment_amount, month, description from capex_payment p join capex_form f on p.capex_id = f.capex_id
Related
I created a table named user_preferences where user preferences have been grouped by user_id and month.
Table:
Each month I collect all user_ids and assign all preferences:
city
district
number of rooms
the maximum price they can spend
The plan assumes displaying a graph showing users' shopping intentions like this:
The blue line is the number of interested users for the selected values in the filters.
The graph should enable filtering by parameters marked in red.
What you see above is a simplified form for clarifying the subject. In fact, there are many more users. Every month, the table increases by several hundred thousand records. The SQL query retrieving data (feeding) for chart lasts up to 50 seconds. It's far too much - I can't afford it.
So, I need to create a table (table/aggregation/data mart) where I will be able to insert the previously calculated numer of interested users for all combinations. Thanks to this, the end user will not have to wait for the data to count.
Details below:
Now the question is - how to create such a table in PostgreSQL?
I know how to write a SQL query that will calculate a specific example.
SELECT
month,
count(DISTINCT user_id) interested_users
FROM
user_preferences
WHERE
month BETWEEN '2020-01' AND '2020-03'
AND city = 'Madrid'
AND district = 'Latina'
AND rooms IN (1,2)
AND price_max BETWEEN 400001 AND 500000
GROUP BY
1
The question is - how to calculate all possible combinations? Can I write multiple nested loop in SQL?
The topic is extremely important to me, I think it will also be useful to others for the future.
I will be extremely grateful for any tips.
Well, base on your query, you have the following filters:
month
city
distirct
rooms
price_max
You can try creating a view with the following structure:
SELECT month
,city
,distirct
,rooms
,price_max
,count(DISTINCT user_id)
FROM user_preferences
GROUP BY month
,city
,distirct
,rooms
,price_max
You can make this view materialized. So, the query behind the view will not be executed when queried. It will behave like table.
When you are adding new records to the base table you will need to refresh the view (unfortunately, posgresql does not support auto-refresh like others):
REFRESH MATERIALIZED VIEW my_view;
or you can scheduled a task.
If you are using only exact search for each field, this will work. But in your example, you have criteria like:
month BETWEEN '2020-01' AND '2020-03'
AND rooms IN (1,2)
AND price_max BETWEEN 400001 AND 500000
In such cases, I usually write the same query but SUM the data from the materialized view. In your case, you are using DISTINCT and this may lead to counting a user multiple times.
If this is a issue, you need to precalculate too many combinations and I doubt this is the answer. Alternatively, you can try to normalize your data - this will improve the performance of the aggregations.
Using Sql management Studio on Sql-Server 2005.
I guess my title is not very clear, so although I'd appreciate a direct answer, even better would be help in reformulating the question that I can search for an answer by myself and learn in the process.
Table A contains yearly total sales for various products. This table is updated once a year in Feb/March.There are two consequences to that: A product that started being sold in, say, July, will obviously only have a six month sale total for the year. Also, any new product will not appear in it before the following year.
Table B is an exception table that gives an estimate for all products not yet in table A or that have a less than a twelve months sale history.
Table C joins the yearly sales with various info from other tables and also contains calculated columns .
In pseudo code what I need is:
Use sales of product x from Table A in table C unless sales for this product exist in table B.
Basically, data from table B should take precedence over table A wether the record exists in A or not.
If you do a LEFT JOIN and no records exist in B, you will get a null for the column values in B. So to "prefer" valued that exist in B, use COALESCE:
SELECT COALESCE(B.Sales, C.Sales) AS Sales
FROM ...
Which loosely translates to "If B has a Sales value, use it, otherwise use the value from C."
Technically it means "take the first non-null value from B.Sales and C.Sales (in that order)"
So, I am totally new to SQL, but the book I have from the courses I take is useless and I am trying to do a project for said course. Internet did not help me all that much (I do not know where to start exactly), so I want to ask for both links to good tutorials to check out as well as help with a very specific piece of query.
If anything I say is not clear enough, please ask me to explain! :)
Suppose two tables sale and p_sale in a database called jewel_store.
sale contains two columns: sale_CODE and sale_date
p_sale contains sale_CODE which references the above sale_ID, p_ID, p_sl_quantity and
p_sl_value
sale_CODE is the primary key of sale and sale_CODE,p_ID is the primary key of p_sale
For the time being p_ID is not of much use so just ignore it for the most part.
p_sl_quantityis int and p_sl_value is double(8,2). The first one is the quantity of the product bought and the second one is the value PER UNIT of the product.
As it probably is obvious a sale_CODE can be linked to a multitude of entries in the p_sale table (example for sale_CODE 1, I have 2 entries on p_sale).
All this is based on what I was given from the task and is correctly implemented and has some example values in.
What I now have to do is find the total income from sales in a specific month. My initial approach was to start structuring everything step by step so I have come to a point that looks like the follows:
SELECT
SUM(p_sl_value * p_sl_quantity) AS sales_monthly_income,
p_sale.sale_CODE
FROM jewel_store.p_sale
GROUP BY p_sale.sale_CODE
This is probably half way through as I can get the total money a sale generated for the store. So my next step was to use this query and SELECT from it. I messed it up a couple of times already and I am scratching my head now. What I did was like this:
SELECT
SUM(sales_monthly_income),
sales_monthly_income,
EXTRACT(MONTH FROM jewel_store.sale.sale_date) AS sales_month
FROM (
SELECT
SUM(p_sl_value * p_sl_quantity) AS sales_monthly_income,
sale_CODE
FROM jewel_store.p_sale
GROUP BY sale_CODE
) as code_income, jewel_store.sale
GROUP BY sales_month
First off, I only need to print the total_montly_income and the month columns in my final form, but I used this to clarify that everything went wrong in there. I think I need to somehow use the foreign key that references the other table, but my book is totally useless in helping me out. I would like someone to explain why this is wrong and what the right one would be and please point me to a good pdf, site or anything to learn how to do this kind of stuff. (I have checked W3SCHOOLS, it is good for the basics, but not for too advanced stuff)
Thanks in advance!
From the top of my head this could be it, group by month the sum of value times quantity.
SELECT
SUM(p.p_sl_value * p.p_sl_quantity) AS sales_monthly_income,
month(s.sale_date)
FROM p_sale p
inner join sale s on s.sale_code = p.sale_code
GROUP BY MONTH(s.sale_date)
I am trying to develop a SQL Server 2005 query but I'm being unsuccessful at the moment. I trying every different approach that I know, like derived tables, sub-queries, CTE's, etc, but I couldn't solve the problem. I won't post the queries I tried here because they involve many other columns and tables, but I will try to explain the problem with a simpler example:
There are two tables: PARTS_SOLD and PARTS_PURCHASED. The first contains products that were sold to customers, and the second contains products that were purchased from suppliers. Both tables contains a foreign key associated with the movement itself, that contains the dates, etc.
Here is the simplified schema:
Table PARTS_SOLD:
part_id
date
other columns
Table PARTS_PURCHASED
part_id
date
other columns
What I need is to join every row in PARTS_SOLD with a unique row from PARTS_PURCHASED, chose by part_id and the maximum "date", where the "date" is equal of before the "date" column from PARTS_PURCHASED. In other words, I need to collect some information from the last purchase event for the item for every event of selling this item.
The problem itself is that I didn't find a way of joining the PARTS_PURCHASED table with PARTS_SOLD table using the column "date" from PARTS_SOLD to limit the MAX(date) of the PARTS_PURCHASED table.
I could have done this with a cursor to solve the problem with the tools I know, but every table has millions of rows, and perhaps using cursors or sub-queries that evaluate a query for every row would make the process very slow.
You aren't going to like my answer. Your database is designed incorrectly which is why you can't get the data back out the way you want. Even using a cursor, you would not get good data from this. Assume that you purchased 5 of part 1 on May 31, 2010. Assume on June 1, you sold ten of part 1. Matching just on date, you would match all ten to the May 31 purchase even though that is clearly not correct, some parts might have been purchased on May 23 and some may have been purchased on July 19, 2008.
If you want to know which purchased part relates to which sold part, your database design should include the PartPurchasedID as part of the PartsSold record and this should be populated at the time of the purchase, not later for reporting when you have 1,000,000 records to sort through.
Perhaps the following would help:
SELECT S.*
FROM PARTS_SOLD S
INNER JOIN (SELECT PART_ID, MAX(DATE)
FROM PARTS_PURCHASED
GROUP BY PART_ID) D
ON (D.PART_ID = S.PART_ID)
WHERE D.DATE <= S.DATE
Share and enjoy.
I'll toss this out there, but it's likely to contain all kinds of mistakes... both because I'm not sure I understand your question and because my SQL is... weak at best. That being said, my thought would be to try something like:
SELECT * FROM PARTS_SOLD
INNER JOIN (SELECT part_id, max(date) AS max_date
FROM PARTS_PURCHASED
GROUP BY part_id) AS subtable
ON PARTS_SOLD.part_id = subtable.part_id
AND PARTS_SOLD.date < subtable.max_date
I am in a mission to devise an application database in MS ACCESS. In my database there are 5 tables:
Master
Cash
Cheque
Detail
Month (displays month in a year)
Here I have made Master as parent record and 3 others Cash, Cheque and Detail are children to Master table.
Here are the fields in master table
Lt no Name Regfee AssessmentYear April May June .......... March
The last 12 fields are months in a financial which takes amount as value.
These values should be populated from cheque/cash table through a query.
cheque
LTno **month** chqueno date bank **amount** are fields.
In this cheque table amount for a particular month is to be populated on master table for the corresponding month. What query do I make.
Expecting your valuable suggestions.
As the database is not normalised, you will have to make a very complicated query to update the table. You have to either make twelve updates that look almost the same, or a huge query that does almost the same thing twelve times.
It would be better to move the month values out of the master table and into a separate table where the month is a field in the table instead of a field name. Then it would be easy to add the records to it:
insert into MasterMonths (LTno, month, value)
select LTno, month, sum(amount)
from cheque
group by LTno, month
I do something similar, except that I include credit card slips and cash purchases as well as checks. It's basic bookkeeping.
For a variety of reasons, I chose to have a table called "almanac" with one row (record) for every date. There are columns (fields) for such things as day of the week, month of the year, and so on. I populate this table with a little code fragment written in VB. Even with ten years worth of dates, that's only about 3,653 rows in the table. I then use simple joins with this table to reduce transaction data to data that's summarized by month. I can summarize in other ways, too.
The query is so easy that I just did it with the graphical query interface. However, my summary would have twelve times as many rows as yours, with only one month in each row.
When I want data laid out in the format of your master table, I use one of two tools: the crosstab query tool in MS Access, or the Pivot Table tool in MS Excel. They are both very powerful, but the pivot tool is more flexible. I had to install an add in called MS query in Excel in order to query database data from Excel. That may be a function of the version I'm using.
This is very different from your framework, and it's your choice whether to use it. It's worked well for me.