How do you comment an MS-access Query? - ms-access

How does one add a comment to an MS Access Query, to provide a description of what it does?
Once added, how can one retrieve such comments programmatically?

I decided to add a condition to the Where Clause that always evaluates true but allows the coder to find your comment.
Select
...
From
...
Where
....
And "Comment: FYI, Access doesn't support normal comments!"<>""
The last line always evaluates to true so it doesn't affect the data returned but allows you to leave a comment for the next guy.

It is not possible to add comments to 'normal' Access queries, that is, a QueryDef in an mdb, which is why a number of people recommend storing the sql for queries in a table.

NOTE: Confirmed with Access 2003, don't know about earlier versions.
For a query in an MDB you can right-click in the query designer (anywhere in the empty space where the tables are), select Properties from the context menu, and enter text in the Description property.
You're limited to 256 characters, but it's better than nothing.
You can get at the description programatically with something like this:
Dim db As Database
Dim qry As QueryDef
Set db = Application.CurrentDb
Set qry = db.QueryDefs("myQuery")
Debug.Print qry.Properties("Description")

I know this question is very old, but I would like to add a few points, strangely omitted:
you can right-click the query in the container, and click properties, and fill that with your description. The text you input that way is also accessible in design view, in the Descrption property
Each field can be documented as well. Just make sure the properties window is open, then click the query field you want to document, and fill the Description (just above the too little known Format property)
It's a bit sad that no product (I know of) documents these query fields descriptions and expressions.

You can add a comment to an MSAccess query as follows: Create a dummy field in the query. Not elegant but is self-documentating and contained in the query, which makes cheking it into source code control alot more feasible! Jere's an example. Go into SQL view and add the dummy field (you can do from design view too):
SELECT "2011-01-21;JTR;Added FIELD02;;2011-01-20;JTR;Added qryHISTORY;;" as qryHISTORY, ...rest of query here...
Run the query:
qryHISTORY FIELD01 FIELD02 ...
2011-01-21;JTR;Added FIELD02;;2011-01-20;JTR;Added qryHISTORY;;" 0000001 ABCDEF ...
Note the use of ";" as field delimiter in qryHISTORY field, and ";;" as an end of comment, and use of ISO date format and intials, as well as comment. Have tested this with up to 646 characters in the qryHISTORY field.

The first answer mentioned how to get the description property programatically. If you're going to bother with program anyway, since the comments in the query are so kludgy, instead of trying to put the comments in the query, maybe it's better to put them in a program and use the program to make all your queries
Dim dbs As DAO.Database
Dim qry As DAO.QueryDef
Set dbs = CurrentDb
'put your comments wherever in your program makes the most sense
dbs.QueryDefs("qryName").SQL = "SELECT whatever.fields FROM whatever_table;"
DoCmd.OpenQuery "qryname"

If you have a query with a lot of criteria, it can be tricky to remember what each one does.
I add a text field into the original table - call it "comments" or "documentation".
Then I include it in the query with a comment for each criteria.
Comments need to be written like like this so that all relevant rows are returned.
Unfortunately, as I'm a new poster, I can't add a screenshot!
So here goes without
Field: | Comment |ContractStatus | ProblemDealtWith | ...... |
Table: | ElecContracts |ElecContracts | ElecContracts | ...... |
Sort:
Show:
Criteria | <> "all problems are | "objection" Or |
| picked up with this | "rejected" Or |
| criteria" OR Is Null | "rolled" |
| OR ""
<> tells the query to choose rows that are not equal to the text you entered, otherwise it will only pick up fields that have text equal to your comment i.e. none!
" " enclose your comment in quotes
OR Is Null OR "" tells your query to include any rows that have no data in the comments field , otherwise it won't return anything!

I've been using the method in the answer by #Dan above for five years, and now realized there's a similar way that allows a comment adjacent to the relevant code, not separated away in a WHERE clause:
A comment can be added in the field code using iif(). For example, if the field code is:
A / B
then it can be commented like so:
iif("Comment: B is never 0." = "", "", A / B)
or
iif(false, "Comment: B is never 0.", A / B)
or
iif(0, "Comment: B is never 0.", A / B)
Like Dan's solution, it's kludgy, but that's SQL's fault.

if you are trying to add a general note to the overall object (query or table etc..)
Access 2016
go to navigation pane, highlight object, right click, select object / table properties, add a note in the description window i.e. inventory "table last last updated 05/31/17"

In the query design:
add a column
enter your comment (in quotes) in the field
uncheck Show
sort in assending.
Note:
If you don't sort, the field will be removed by access. So, make sure you've unchecked show and sorted the column.

Related

Returning specific field from a matching record

I'm still a newbie at Access 2007, but I feel I am missing a understanding of a concept, when it comes to using user input from an unbound text box.
I'm trying to have the user input the record number (i.e. A12) and return another field in the matching record (such as the record status like "Opened")
I'm fiddling with DLookup to see if it will work through that method but no luck yet.
I may look into SELECT - SQL, but I haven't used that function yet and not sure if that will give me the result I'm looking for.
If this is something elementary to access programming (or databases in general), please let me know where I can read up on this.
I am currently using the MSDN website, but examples go much further to play with.
Edit:
My DLookup so far, which happens after update from user on Text12
Me.Text14.Value = DLookup("[RecordStatus]", "Orders", Text12.Value)
Thanks
Look closer at the third option (Criteria) in your DLookup() expression. You gave it only Text12.Value, which I assume is a string value like "A12".
The Criteria parameter should be like a WHERE clause in a query, without the word WHERE. IOW, some field's value = "A12". If that field is named "record_id", try this:
DLookup("RecordStatus", "Orders", "record_id = '" & Me.Text12 & "'")

How do I change the values of a radio button from 1, 2, 3, etc to text values?

I have created a small database in Access 2007 that consists of one table and two forms, one for entering data, and one for retrieving data.
My problem is this: On my input form I have a group box with three radio buttons in it. The question being asked is Is the element a sensor?
The buttons represent Yes, No, and Don’t Know.
In the database I have a column named Sensor to hold the value the user chose, but since the radio buttons return a value of 1 for yes, 2 for no, or 3 for don't know, it makes generating a report or query that makes sense to the user very difficult.
At this point I’m writing huge SQL statements with nested iif’s to return the data the way I want to see it.
Is there a way to populate the table with data the way I want to see it (yes, no, don’t know) instead of populating it with 1’s 2’s or 3’s? This is a bound form by the way, I wish I would have done it unbound, but I can’t go back now.
I would suggest not using the radio buttons, and instead opt for a combo box. You'll be able to use string values for the results directly in the combo box.
Now if you are dead set on using radio buttons, try this:
Add a new field to your table that holds text. Bind this to a hidden text box on your form.
Then, add a BeforeUpdate event (or AfterUpdate depending on what you are doing) to the radio group. Add code similar to the following:
Sub RadioGroup_BeforeUpdate(cancel As Integer)
Select Case Me.RadioGroup.Value
case 1
Me.hiddenTextField.value = "Yes"
case 2
Me.hiddenTextField.value = "No"
case else
Me.hiddenTextField.value = "Don't Know"
End Select
End Sub
Now when you save the record, the human readable value will be available in the new field you added.
"since the radio buttons return a value of 1 for yes, 2 for no, or 3 for don't know, it makes generating a report or query that makes sense to the user very difficult."
Store those 3 pairs as rows in a Sensor_Values table:
sval descriptor
1 yes
2 no
3 don't know
Then you can join that table to the table which includes the stored Sensor numbers.
SELECT yt.Sensor, sv.descriptor
FROM
YourTable AS yt
INNER JOIN Sensor_Values AS sv
ON yt.Sensor = sv.sval;
If you're opposed to creating and joining a lookup table, you could use a Switch() expression in your queries to translate the numeric Sensor values to their text forms.
SELECT
Switch(
Sensor = 1, "yes",
Sensor = 2, "no",
Sensor = 3, "don't know"
) AS sensor_text
FROM YourTable;
The Switch() approach can work, but can be more challenging to maintain compared to the lookup table approach.
My intention here was to show you fairly simple methods to use the option group value as a number instead of "populate the table with data the way I want to see it (yes, no, don’t know) instead of populating it with 1’s 2’s or 3’s"
As a general rule, you will be better off working with Access controls as they were designed to be used. Break that rule whenever you have a compelling reason ... but breaking the rule then requires additional efforts from you ... like more VBA code. The approaches I suggested don't require any VBA.
you could use a Select Case when creating the select string, instead of having iif's nested in the SQL.
Select Case Me.rdoSensor
Case 1
sSQL=sSQL & " AND Sensor='Yes'"
Case 2
sSQL=sSQL & " AND Sensor='No'"
Case 3
sSQL=sSQL & " AND Sensor='Don''t know'"
End Select

Efficient use of calculations in MS Access

This is the kind of thing I feel I should already know, but don't...
In MS Access, if a query consists of n calculated fields (say calc_1, calc_2, .... calc_n) but I only want to use a subset of them in a particular form or report - say calc_x, calc_y and calc_z - would Access calculate all n calculations when running SELECT calc_x, calc_y, calc_z FROM myquery and then return the ones I want, or would it be smart enough to only calculate calc_x, calc_y and calc_z?
In my case I'm using Access 2003 but presumably the answer is the same for all versions.
Access is smart and don't calculate not-visible fields.
Tried with Access 2003
Like #David, I did not believe #Andreas's answer at first. So I tested it myself as follows. I created the following function:
Function Watch(Val, Optional CalledFrom As String = "")
Debug.Print Val, CalledFrom
Watch = Val
End Function
Then I created a table named "Dummy" with a single field named "ID". I created a form and used the following as the form's RecordSource:
SELECT Watch([ID],"ShowInForm") AS ShowInForm,
Watch([ID],"HideFromForm") AS HideFromForm
FROM Dummy;
I added a single textbox control with a ControlSource of ShowInForm.
I then opened the form and got this in the immediate window:
1 ShowInForm
1 ShowInForm
1 ShowInForm
I then went back to the RecordSource and previewed it in Datasheet view and got this:
1 ShowInForm
1 HideFromForm
I'm not sure why the "ShowInForm" expression is evaluated three times in the form, but it seems pretty clear that the unused field, "HideFromForm", does not get evaluated.
To address #HansUp's comment, I went back and saved a query named "Qry":
SELECT Watch([ID],"ShowInForm") AS ShowInForm,
Watch([ID],"HideFromForm") AS HideFromForm
FROM Dummy;
Then changed the form RecordSource to:
Select ShowInForm FROM Qry
This produced the same result as before when I opened the form (ie, 3 lines of 1 ShowInForm). Interestingly, when I opened the RecordSource in datasheet view I got this:
1 ShowInForm
1 ShowInForm
In other words, it evaluated the ShowInForm field twice. Presumably, once in "Qry" and again in the RecordSource query.
The end result is still a confirmation of #Andreas's answer.
If you include the calculated fields in the SELECT clause of your report or form's recordsource, it will calculate them for each row AS IT IS RETRIEVED.
If you leave them out of the SELECT and include the calculations only in the ControlSource properties of controls on your report/form, then what you say is true.
Also, if you do any sorting/grouping on the calculations or put criteria on them, all rows will be calculated.
Thus, in this recordsource:
SELECT Field1/Field2 As Ratio1, Field3/Field4 As Ratio2, FIeld1, Field2, Field3, Field4
FROM MyTable;
...for each row that is retrieved, both calculations will be executed regardless of whether or not the result is used in the form or report.
If you want to delay calculations to the last possible moment, do NOT include them in the SQL recordsource, but just use them as the ControlSources of the controls that are displaying the calculations. However, this has the downside that you'll see the calculations painting onscreen in many cases.
EDIT:
It seems this may not be correct, but I feel there's something going on here that is not completely explained by #mwolfe02's answer. I'll just leave this here for further discussion.
I put calculations like this on the server side.. computed columns are awesome.
I think that Access finally got this feature in 2007, I don't know how people ever survived without it.

Ms access: Autocomplete field with values from another table

please forgive me for my poor english and my big ignorance on programming.
I'm using Ms Access 2003.
Let's suppose i have two tables:
Table1: ID (autonumber), [...], Keywords (memo)
Table2: ID (autonumber), Keyword (text)
I want:
1) As the user types letters in Table1.Keywords that my database searches in Table2.keyword for the nearest value and proposes it by autocompleting (just like google proposes a search word as you type)
2) When user presses ", " that he can add one more keyword in the same field (and the autocomplete still runs for this next value)
3) If he types a keyword not included in Table2 and press ", " that he is asked if he wants this value to be added in Table2
Well, i'm not sure if all these are clear... maybe they are a lot of things...
But i'd appreciate if you could help me...
Thanks in advance
J.
It would be complicated to do it with a single control, but with two controls, a dropdown list for choosing the value to add, and a textbox displaying the memo field, you could have the combo box's AfterUpdate event append a comma and the chosen value to the existing data. Something like this:
Private Sub cmbChooseKeyword_AfterUpdate()
If Not IsNull(me!cmbChooseKeyword) Then
Me!txtKeywordMemo = (Me!txtKeywordMemo + ", ") & Me!cmbChooseKeyword
End If
End Sub
You'd also want the rowsource of your combo box to not list items that are already entered, so this is one way that would work for a relatively short list of keywords:
SELECT tblKeywords.*
FROM tblKeywords
WHERE InStr(Forms!MyForm!txtKeywordMemo, tblKeywords.Keyword) = 0;
Then you'd add:
Me.Dirty = False
Me!cmbChooseKeyword.Requery
...at the end of the AfterUpdate code above (inside the End If):
Private Sub cmbChooseKeyword_AfterUpdate()
If Not IsNull(me!cmbChooseKeyword) Then
Me!txtKeywordMemo = (Me!txtKeywordMemo + ", ") & Me!cmbChooseKeyword
Me.Dirty = False
Me!cmbChooseKeyword.Requery
End If
End Sub
...and you'd want to add the requery to the OnCurrent event of your form, as well (so that when you arrive on a record, the combo box already omits any keywords that are already in the list).
Now, all that said, I'd completely recommend against doing this. This is a denormalized way to store the data, and this leads to problems:
what if you want to delete one keyword?
what if you want the keywords to be sorted in alphabeticsal order?
what if you have 100s of thousands of records and you want to search this field with LIKE "*Keyword*" -- will it bog down to be terribly slow (no indexes, and not used well even if there were)?
You really should use a proper many-to-many structure, with an additional table between the one where you're currently storing the keyword memo and your keyword list table. This "joins" the two, and would then give you a list.
You could then use a subform with a dropdown list to populate each row of the join table.
If you like presenting the keywords on reports as a comma-separated list (as you're currently storing them), you can write a simple function to do the concatenation for you at the presentation layer of your reports (concatenation functions for that purpose are a frequent Access question here on Stackoverflow).
Why not use a "Combo Box" and set its Row Source Type to Table/Query, and then make the Row Source a query on the second table. Just make sure you don't turn on Limit to List.
CodeSlave mentions a way that will work. But it will only work for one value. There is no way to do the multi-words-separated-by-commas thing. Only one word at a time.
As for the Adding new values. The combobox control support an OnNotInList event which can do what you say.
Seth

How can I display a *foreign* field value in a text box?

How do I bind a text box with a field, which doesn't belong to form's "Record Source" table, through the Design View?
Example: I have "Order.cust_id" (Record Source=Order) and I want to display "Customers.name". I believe it is trivial but I have no experience with MS Access. I tried to use the text box "Control Source" property but no luck.
One method would be to convert the text box to a combo box. Then set the row source to include both the cust_Id and the Customer.Name from the customer table. SQL statement example
Select Cust_ID, Name From Customer
Order By Name;
By setting the number of columns to 2 and the column widths; the first column as zero (i.e. "0;6") then the foreign key would be hidden from the user and the customer name would be displayed.
Note this method does force you to have limit to list set to true.
Also you do end up with a drop down list which may not be what you want.
You can use DlookUp as the control source of a textbox:
=DlookUp("[Name]", "Customer", "ID=" & Cust_ID)
Syntax: What to look up, table name, where statement
The Where statement should follow the rules for Jet SQL, which means that you must use delimiters if the field is text or date format.
Note that Name is a very bad name indeed for anything. I suggest you rename the field immediately before things get worse.
It can be useful to know the error(s).
You could create a new View (e.g. OrdersAndCustomerNames), select all the columns you want to use in the form, then instead of using the Order table as Record Source, you would just switch to OrdersAndCustomerNames. You say you have no experience with MS Access, so I am guessing you are not building anything huge and overly complicated, so I would do it this way. I am quite sure it can be done more elegantly but this will do for now.