I'm new to access and I'm struggling on how to use lookups since vlookup is not available in Access. I want to get the values that correspond to a certain ID/tagging.
I have 2 tables.
Table A contains values let's say Product Number, Product Type, Price, Remaining Stock #, Product Type+Product Number Tag. Let's say product number is not unique but combining it with its product type, it will be unique so I created that tag.
Table B contains Seller's Name, # of items Sold, Product Number, Product Type, Product Type+Product Number Tag.
Now using Table A and Table B, how can I create a query/table that will allow me to use that "Product Number + Product Type" Tag when I try to get the price of that certain item so that I can get the total revenue of each seller.
I hope you understand what I'm trying to say. What I just want to do is I want to use this "Type+Number" Tag as a reference point in getting data of that respective item when I try to create queries/tables. It's just like an INDEX/MATCH in Excel. But how to do it in Access?
Please tell me if it's unclear.
Thank you!
You need to join your two tables based on the relationship between the Product Number & Product Type fields in both tables.
The two fields in Table A should be marked as the composite Primary Key (select both fields and in the Design ribbon click the Primary Key icon).
In Table B they will be Foreign Keys - a seller could sell those products more than once, so duplicates are allowed here.
You don't need the Product Type+Product Number Tag field.
The SQL for your query would then be:
SELECT *
FROM [Table A] LEFT JOIN [Table B] ON [Table A].[Product Number] = [Table B].[Product Number] AND
[Table A].[Product Type] = [Table B].[Product Type]
This will return all records from Table A and only those records from Table B that match the Primary Key.
Finally.... don't think of an Access table as an Excel spreadsheet. Access is all about the relationship between pieces of data - for a start queries can be expressed in plain English a lot easier.
E.g return all records from table B where seller name is "Dave" and date is between 1st Jan and 31st Jan would be written as:
SELECT *
FROM [Table B]
WHERE [Seller Name]='Dave' AND
[Sale Date] Between #01/01/2018# AND #01/31/2018#
(SQL only deals in US date format).
You can use DlookUp Function.
It can be used on queries as a calculated field, or in code in VBA:
For example, to get the price of a PRoduct, you could use something like:
DlookUp("[Price]";"Table A";"[Product Type+Product Number Tag]='" & Value & "'")
From my point of view, the complex part of DlookUp is the third argument, the WHERE clausule. If you have any experience with SQL, you will have no problem. If you don't, don't worry, just read some info and if you get stuck, come here to SO
You can use DlookUp to get any value of any field, based on a criteria (criteria applied to a unique field, ofc).
And yes, you can use it to get values from tables or from queries. In the link I provided before, it explains how the arguments works.
The most complex part is the criteria part. You must write as if you were typing a WHERE clausule on SQL more info here
About the criteria, always remember this:
If your criteria is a numeric value, then just type [field_criteria]=my_numeric_criteria
If your criteria is a text value, you must use single quotes. For example, [field_criteria]='my_text_criteria'
SQL requires single quotes around text values.
Try it!
Related
I have two tables:
'tableStudent' - a list of students given an ID number by the table, with following columns:
student_ID
last_name
first_name
and 'tableProject' which gives each project an ID and will be used to store information about the students involved in the project. Students will work in pairs on the project. This table includes the following columns:
project_ID
project_title
student1_ID
student2_ID
The columns student1_ID and student2_ID are combo-boxes that link student_ID to the student names.
I want to create a form that can be used to record students involved in a project. I want to be able to select the student IDs and have the student names autofill on a form.
I can make a form that autofills, but only with one student with this SQL:
SELECT tableProject.project_ID, tableProject.project_title, tableProject.student1_ID, tableStudent.last_name, tableStudent.first_name
FROM tableStudent INNER JOIN tableProject ON (tableStudent.student_ID = tableProject.student2_ID) AND (tableStudent.student_ID = tableProject.student1_ID);
When I add Student 2, I get a duplicate error on the student names. How do I indicate that the two names belong to different students? This is the code I'm generating:
SELECT tableProject.project_ID, tableProject.project_title, tableProject.student1_ID, tableStudent.last_name, tableStudent.first_name, tableProject.student2_ID, tableStudent.last_name, tableStudent.first_name
FROM tableStudent INNER JOIN tableProject ON (tableStudent.student_ID = tableProject.student2_ID) AND (tableStudent.student_ID = tableProject.student1_ID);
Any help appreciated!
Options for displaying related info from lookup table:
Use Access query designer to build form RecordSource. Pull tableStudent into query designer. In your case pull in twice - second instance will get named like tableStudent_1. Join each to one of the student fields. Bind textboxes to both sets of lookup table fields and set them as Locked Yes to prevent edit.
Don't include lookup table in form RecordSource at all. Include all student info in combobox RowSource. Expressions in textboxes refer to combobox columns by index, index begins with 0: =[comboboxName].Column(1)
DLookup() domain aggregate function, however, since your tables have a relationship, this is an inefficient method.
For all options, set textboxes with TabStop No.
I have a table that has Act ID, and another table that has Act ID, percentage complete. This can have multiple entries for different days. I need the sum of the percentage added for the Act ID on the first tableZA.108381.080
First table
Act ID Percent Date
ZA.108381.110 Total from 2 table
ZA.108381.120
ZA.108476.020
ZA.108381.110 25% 5/25/19
ZA.108381.110 75 6/1/19
ZA.108381.120
ZA.108476.020
This would be generally considering not good practice. Your primary key should be uniquely identifiable for that specific table, and any other data related to that key should be stored in separate columns.
However since an answer is not a place for a lecture, if you want to store multiple values in you Act ID column, I would suggest changing your primary key to something more generic "RowID". Then using vba to insert multiple values into this field.
However changing the primary key late in a databases life may cause alot of issues or be difficult. So good luck
Storing calculated values in a table has the disadvantage that these entries may become outdated as the other table is updated. It is preferable to query the tables on the fly to always get uptodate results
SELECT A.ActID, SUM(B.Percentage) AS SumPercent
FROM
table1 A
LEFT JOIN table2 B
ON A.ActID = B.ActID
GROUP BY A.ActID
ORDER BY A.ActID
This query allows you to add additional columns from the first table. If you only need the ActID from table 1, then you can simplify the query, and instead take it from table 2:
SELECT ActID, SUM(Percentage) AS SumPercent
FROM table2
GROUP BY ActID
ORDER BY ActID
If you have spaces other other special characters in a column or table name, you must escape it with []. E.g. [Act ID].
Do not change the IDs in the table. If you want to have the result displayed as the ID merged with the sum, change the query to
SELECT A.ActID & "." & Format(SUM(B.Percentage), "0.000") AS Result
FROM ...
See also: SQL GROUP BY Statement (w3schools)
I have a query i have been working on trying to get a specific set of data, join the comments in duplicate phone numbers of said data, then join separate tables based on a common field "entry_id" which also happens to be the number on the end of the word custom_ to pull up that table.
table named list and tables containing the values i want to join is custom_entry_id (with entry_id being a field in list in which i need the values of each record to replace the words in order to pull up that specific table) i need entry_id from the beginning part of my query to stick onto the end of the word custom for every value my search returns to get the fields from that custom table designated for that record. so it will have to do some sort of loop i guess? sorry like i said I am at a loss at this point
this is where i am so far:
SELECT * ,
group_concat(comments SEPARATOR '\r\n\r\n') AS comments_combined
FROM list WHERE `status` IN ("SALEA","SALE")
GROUP BY phone_number
//entry_id is included in the * as well as status
// group concat combines the comments if numbers are same
i have also experimented on test data with doing a full outer join which doesnt really exist. i feel if you can solve the other part for me i can do the joining of the data with a query similar to this.
SELECT * FROM test
LEFT JOIN custom_sally ON test.num = custom_sally.num
UNION
SELECT * FROM test
RIGHT JOIN custom_sally ON test.num = custom_sally.num
i would like all of this to appear with every field from my list table in addition to all the fields in the custom_'entry_id' tables for each specific record. I am ok with values being null for records that have different custom fields. so if record 1 has custom fields after the join of hats and trousers and record 2 has socks and shoes i realize that socks and shoes for record 1 will be null and hats and trousers for record 2 will be null.
i am doing all this in phpmyadmin under the SQL tab.
if that is a mistake please advise as well. i am using it because ive only been working with SQl for a few months. from what i read its the rookie tool.
i might be going about this all wrong if so please advise
an example
i query list with my query i get 20,000 rows with columns like status, phone_number, comments, entry_id, name, address, so on.
now i want to join this query with custom fields in another table.
the problem is the custom tables' names are all linked to the entry_id.
so if entry_id is 777 then the custom table fields are custom_777
my database has over 100 custom tables with specials fields for each record depending on its entry_id.
when i query the records I don't know how to join the custom fields that are entry_id specific to the rest of my data.i will pull up some tables and data for a better example
this is the list table:
this is the custom_"entry_id"
Full Outer Join in MySQL
for info on full outer joins.
I've created a stock control database which contains two tables (actually more than two, but these are the two that are relevant to my question): Stock, and Receipts
I would like the link between the stock in the stock table,and the stock in the receipts table to be a little more clearer, this would be fine if a customer could only order one item of stock per receipt, as i'd simply have a StockID column and a Quantity column in the Recipts table, with the StockID column as an FK to the ID in the Stock table, however, the customer can make a receipt with any number of items of stock on it, which would mean i'd have to have a large number of columns in the Receipts table (i.e. StockID_1, Quantity_1, StockID_2, Quantity_2 etc.)
Is there a way around this (can you have like a dynamically expanding set of columns in MySQL) within MySQL, other than what i've done at the moment, which is to have an OrderContents column with the following structure (which isn't enforced by the database or anything) StockID1xQuantity,StockID2xQuantity and so on?
I would post an image of the DB structure, but I don't have enough repuation yet. My lecturer mentioned something about that it could be done, by normalising the database into 4th or 5th normal form?
I'd suggest having 3 tables:
Stock (StockID) + stock specific fields
Receipt (ReceiptID) + receipt specific fields.
StockReceipt (ReceiptID, StockID, Quantity) (could have a StockReceiptID, or use StockID+ReceiptID as Primary Key)
A solution including prices could look like:
Stock (StockID, Price)
PriceHistory (StockID, Price, Date) or (DateFrom, DateTo)
Receipt (ReceiptID, ReceiptDate)
StockReceipt (ReceiptID, StockID, Quantity)
That way you can calculate TotalStockReceiptPrice and TotalReceiptPrice for any receipt in the past.
I suspect this might be what you're looking for:
Stock (StockID, StockPrice)
Receipt (ReceiptID)
StockReceipt (ReceiptID, StockID, Quantity)
SELECT r.ReceiptID, SUM(s.StockPrice * sr.Quantity) AS ReceiptPrice
FROM Receipt r
INNER JOIN StockReceipt sr ON r.ReceiptID = sr.ReceiptID
INNER JOIN Stock s ON sr.StockID = s.StockID
GROUP BY r.ReceiptID
This is all very normalised (again, no idea to what normal form - 3rd?). However it only works if the StockPrice on the Stock record NEVER changes. As soon as it changes your ReceiptPrices would all reflect the new price instead of what the customer actually paid.
If the price can change, you'd need to either keep a price history table (ItemID, Price, DateTo, DateFrom) or record the StockPrice on the StockReceipt record (and then get rid of the JOIN to the Stock record in the above query and make it use sr.StockPrice instead of s.StockPrice)
To do the INSERT you posted below, you'd have to do:
INSERT INTO StockReceipts (ReceiptID, StockID, Quantity, TotalStockPrice)
SELECT 1, 99, 2, s.StockPrice
FROM Stock s
WHERE s.StockID = 99
However it's quite likely that whatever is issuing this receipt (and triggers the INSERT) already knows the price so could just insert the value.
No, relational databases do not allow dynamic columns. The definition of a relational table is that it has a header that name the columns, and every row has the same columns.
Your technique of repeating the groups of stock columns is a violation of First Normal Form, and it also has a lot of practical problems, for instance:
How do you know how many extra columns to create?
How do you search for a given value when you don't know which column it's in?
How do you enforce uniqueness?
The simplest solution is as #OGHaza described, store extra stock/quantity data on rows in another table. That way the problems above are solved.
You don't need to create extra columns, just extra rows, which is easy with INSERT.
You can search for a given value over one column to find it.
You can put constraints on the column.
If you really want to understand relational concepts, a nice book that is easy to read is: SQL and Relational Theory: How to Write Accurate SQL Code by C. J. Date.
There are also situations where you want to expand a table definition with dynamic columns that aren't repeating -- they're just new attributes. This is not relational, but it doesn't mean that we don't need some data modeling techniques to handle the scenario you describe.
For this type of problem, you might like to read my presentation Extensible Data Modeling with MySQL, for an overview of different solutions, and their pros and cons.
PS: Fourth and Fifth normal form have nothing to do with this scenario. Your lecturer obviously doesn't understand them.
Is it possible to build an unmatched data query using two tables with a tracking a unique value field and also another value in the row as well (that value will not be unique).
For example I want to track a unique customer code from an invoice on a new table, compared to last month's invoice. The non unique value would be a "product code" of what they purchased.
A customer code could appear multiple times depending on if they have purchased multiple product codes.
Any help is much appreciated.
This should do what you want:
SELECT Invoice.CustomerID
FROM Invoice LEFT JOIN PreviousInvoices
ON (Invoice.Product = PreviousInvoices.Product)
AND (Invoice.CustomerID = PreviousInvoices.CustomerID)
WHERE PreviousInvoices.Product Is Null