I have a situation like - the customer form in MS access 2007 have list of documents provided by customers. The list is in the checklist format. Assuming there are 6 documents under the checklist. So if the one or more checklists are selected, all the selected list should be saved in the database column named "Documents_Provided". So in order to achieve this scenario what should I have to do. How should my database field "Documents_provided" should be declared and what do I have to write in VBA code.
As per your Question heading suggests "Multiple to be stored in a Column of the database" is a very bad table design, it breaks one of the rules of Fundamentals of Database Design, Data should be atomic.
The system you should be having is a One to Many, between the Customer and Document table. The Customer table will normally have the basic customer information; one side of the relationship, and the Documents table will have all the documents that pertain to each Customer; many side of the relationship. In Addition you will have another table Document Category that will say what are all the documents that needs/can have for each customer. So sample data in your table will be something like,
tbl_Customers
`````````````
ID | customerName | customerArea
----+-------------------+------------------
1 | Paul | Bournemouth
2 | Eugin | Bristol
3 | Francis | London
tbl_DocumentsCategory
`````````````````````
ID | DocumentName
----+---------------------------
1 | Address Proof
2 | Photo ID
3 | Employer Certificate
tbl_CustomersDocument
`````````````````````
ID | CustomerID | DocumentID
----+---------------+--------------
1 | 1 | 1
2 | 1 | 2
3 | 1 | 3
4 | 2 | 1
5 | 2 | 3
6 | 3 | 2
So when you need to get the list of Documents each Customer has, you simply JOIN the two tables to get the right information. This is the standard and efficient way to organize the data. I hope this helps, and you stick to this.
Related
How can we auto generate column/fields in microsoft access table ?
Scenario......
I have a table with personal details of my employee (EmployDetails)
I wants to put their everyday attendance in an another table.
Rather using separate records for everyday, I want to use a single record for an employ..
Eg : I wants to create a table with fields like below
EmployID, 01Jan2020, 02Jan2020, 03Jan2020,.........25May2020 and so on.......
It means everyday I have to generate a column automatically...
Can anybody help me ?
Generally you would define columns manually (whether that is through a UI or SQL).
With the information given I think the proper solution is to have two tables.
You have your "EmployDetails" which you would put their general info (name, contact information etc), and the key which would be the employee ID (unique, can be autogenerated or manual, just needs to be unique)
You would have a second table with a foreign key to the empployee ID in "EmployDetails" with a column called Date, and another called details (or whatever you are trying to capture in your date column idea).
Then you simply add rows for each day. Then you do a join query between the tables to look up all the "days" for an employee. This is called normalisation and how relational databases (such as Access) are designed to be used.
Employee Table:
EmpID | NAME | CONTACT
----------------------
1 | Jim | 222-2222
2 | Jan | 555-5555
Detail table:
DetailID | EmpID (foreign key) | Date | Hours_worked | Notes
-------------------------------------------------------------
10231 | 1 | 01Jan2020| 5 | Lazy Jim took off early
10233 | 2 | 02Jan2020| 8 | Jan is a hard worker
10240 | 1 | 02Jan2020| 7.5 | Finally he stays a full day
To find what Jim worked you do a join:
SELECT Employee.EmpID, Employee.Name, Details.Date, Details.Hours_worked, Details.Notes
FROM Employee
JOIN Details ON Employee.EmpID=Details.EmpID;
Of course this will give you a normalised result (which is generally what's wanted so you can iterate over it):
EmpID | NAME | Date | Hours_worked | Notes
-----------------------------------------------
1 | Jim | 01Jan2020 | 5 | ......
1 | Jim | 02Jan2020 | 7 | .......
If you want the results denormalised you'll have to look into pivot tables.
See more on creating foreign keys
I am facing an issue where a data supplier is generating a dump of his multi-tenant databases in a single table. Recreating the original tables is not impossible, the problem is I am receiving millions of rows every day. Recreating everything, every day, is out of question.
Until now, I was using SSIS to do so, with a lookup-intensive approach. In the past year, my virtual machine went from having 2 GB of ram to 128, and still growing.
Let me explain the disgrace:
Imagine a database where users have posts, and posts have comments. In my real scenario, I am talking about 7 distinct tables. Analyzing a few rows, I have the following:
+-----+------+------+--------+------+-----------+------+----------------+
| Id* | T_Id | U_Id | U_Name | P_Id | P_Content | C_Id | C_Content |
+-----+------+------+--------+------+-----------+------+----------------+
| 1 | 1 | 1 | john | 1 | hello | 1 | hello answer 1 |
| 2 | 1 | 2 | maria | 2 | cake | 2 | cake answer 1 |
| 3 | 2 | 1 | pablo | 1 | hello | 1 | hello answer 3 |
| 4 | 2 | 1 | pablo | 2 | hello | 2 | hello answer 2 |
| 5 | 1 | 1 | john | 3 | nosql | 3 | nosql answer 1 |
+-----+------+------+--------+------+-----------+------+----------------+
the Id is from my table
T_Id is the "tenant" Id, which identifies multiple databases
I have imagined the following possible solution:
I make a query that selects non-existent Ids for each table, such as:
SELECT DISTINCT n.t_id,
n.c_id,
n.c_content
FROM mytable n
WHERE n.id > 4
AND NOT EXISTS (SELECT 1
FROM mytable o
WHERE o.id <= 4
AND n.t_id = o.t_id
AND n.c_id = o.c_id)
This way, I am able to select only the new occurrences whenever a new Id of a table is found. Although it works, it may perform badly when working with 100s of millions of rows.
Could anyone share a suggestion? I am quite lost.
Thanks in advance.
EDIT > my question is vague
My final intent is to rebuild the tables from the dump, incrementally, avoiding lookups outside the database. Every now and then I am gonna run a script that will select new tenants, users, posts and comments and add them to their corresponding tables.
My previous solution worked as follows:
Cache the whole database
For each new row, search for the columns inside the cache
If it doesn't exist, then insert it
I know it sounds dumb, but it made sense as a new developer working with ETLs
First, if you have a full flat DB dump, I'll suggest you to work on your file before even importing it in your DB (low level file processing is pretty cheap and nearly instantaneous).
From Removing lines in one file that are present in another file using python you can remove all the already parsed line since your last run.
with open('new.csv','r') as source:
lines_src = source.readlines()
with open('old.csv','r') as f:
lines_f = f.readlines()
destination = open('diff_add.csv',"w")
for data in lines_src:
if data not in lines_f:
destination.write(data)
destination.close()
This take less than five second to work on a 900Mo => 1.2Go dump. With this you'll only work with line that really make change in one of your new table.
Now you can import this flat DB to a working table.
As you'll have to search the needle in each line, some index on the ids may by a good idea (go to composite index that use your Tenant_id first).
For the last part, I don't know exactly how your data look, can you have some update to do ?
The Operators - EXCEPT and INTERSECT can help you too with this kind of problem.
I have several tables in Microsoft Access 2013, all of which follow the same format of:
ID | Object | Person 1 | Person 2 | Person 3 |
ID | String | Yes/No | Yes/No | Yes/No |
What I would like to do is make a query where I put in a string value for each table and it prints out the entire row, with each string getting its own row, so it looks like:
ID Number | Object | Person 1...
Table 1 ID | Table 1 String | Table 1 Yes/No...
Table 2 ID | Table 2 String | Table 2 Yes/No...
Every time I try, though, it puts all the data into one extremely long row that's impossible to look at. All of my searching has only turned up people trying to do the exact opposite of what I'm doing, though, so I must be missing something obvious. Any tips?
I'm trying to build a database with multiple tables for a study/research. This is the first time I'm designing database of this magnitude; the database grows by 100-200 records a day, and so far I have the data since 2010. Out of all the data, Generic Sequence Number, Product Name and the Strength of a drug (prescription) is slightly bothering me. This is what I have done so far:
Generic Seq number is unique to the strength of drug (product name). So, I have a table that contains id, generic seq no, and strength. Another table is for prod_id and product name. Each Generic seq number may have one or more product name, and each product name may have different generic seq number based on the strength. So, I set it up as many-to-many relationship. I created another table for this relationship that contains rx_id, drug_id, and prod_id. Since many patients may be prescribed for the same drug, the drug_id and prod_id may repeat several times in the rx_table.
My first question is, is this design appropriate?
How should I insert the data into rx_table? Should I create new record every time for new data even if the drug_id and prod_id already exist in the rx_table, or should I look for the rx_id where the drug_id and prod_id sequence exist and insert the rx_id into the other main table (not shown) which contains other data.
Or is this question too vague?
Thank you for your help.
I don't know what exactly is your Generic Sequence Number so i'll just use a real life drug example. From your description i think it's pretty similar to your application. Lets say you have Paracetamol as an agent. Then your Generic Sequence Number table would be something like
drug_id | generic_seq_no | strength
--------+--------------------+----------
1 | Paracetamol-100 | 100
2 | Paracetamol-250 | 250
3 | Paracetamol-500 | 500
Your product table would contain the names of the trademarks:
prod_id | prod_name
----------+------------
1 | Tylenol
2 | Captin
3 | Panadol
the rx_table contains the combinations of trademark name, agent and strength:
rx_id | drug_id | prod_id
-------+----------+----------
1 | 1 | 1
2 | 1 | 2
3 | 1 | 3
4 | 2 | 1
5 | 2 | 2
6 | 3 | 2
7 | 3 | 3
So e.g. the first row would be Tylenol, containing 100 mg of Paracetamol. Now you have what can be prescribed by a doctor and that's what you already did so far. So as i said your approach is fine.
Now you need (or have?) another table with all your patients
patient_id | firstname | lastname
-----------+-----------+-----------
1 | John | Doe
2 | Jane | Doe
In the end, you must link your trademark/agent/strength combination to the patients. Since one patient may get different drugs and multiple patients may get the same drug you need another many-to-many-relation, let's call it prescription
prescription_id | patient_id | rx_id
----------------+------------+------
1 | 1 | 1
2 | 1 | 3
3 | 2 | 4
This means John Doe will get Tylenol and Panadol containing 100 mg Paracetamol each. Jane Doe will receive Tylenol with 250 mg Paracetamol. I think the table you will be inserting the most is the prescription table in this model.
My SQL Server 2008 table is constructed as follows:
160 columns consisting of a Ratio_ID and 160 companies as headers
742 rows consisting of the Ratio_ID's per company.
The typical structure would be:
Ratio_ID | Company 1 | Company 2 | To Company 160
part03x0 | 0.01 | 0.03 |
To Ratio_ID742 |
How would I be able to run a Query to request All Companies Where Ratio_ID part03x0 is zero?
Tried to Google this, but explaining it is very difficult.
Hope it makes sense!
Why are you storing the companies as columns? The companies should be placed in their own table, with a unique ID referring to each company. You can than use this ID with the Ratio_ID in order to perform the query.
160 columns is a massive overkill. Here is a nice tutorial on how to normalize your database.
EDIT:
You do not need to have a table for each company. You only need one table named, for example, tbl_Company and just add the following:
company_id | company_name
1 | CompanyNameOne
2 | CompanyNameTwo
3 | CompanyNameThree
Another table for your Ratios, tbl_Ratio
ratio_id | ratio_name
1 | RatioNameOne
2 | RatioNameTwo
Then combine both using ForeignKeys and Relationships between the two tables into a separate table as below:
tbl_Company_Ratio
company_id | ratio_id | ratio_amount
1 2 5
1 1 2
3 2 10
2 2 5
....