Make interval list between two date in vba - vba

Question

I want to make a list look like below to insert into a table between two date range:
make_intervals_list ('2016-01-01','2020-12-31');
+----------------+--------------+--------+
| interval_start | interval_end | rate |
+----------------+--------------+--------+
| 2016-01-01 | 2016-12-31 | 95 |
| 2017-01-01 | 2017-12-31 | 105 |
| 2018-01-01 | 2018-12-31 | 115 |
| 2019-01-01 | 2019-12-31 | 125 |
| 2020-01-01 | 2020-12-31 | 135 |
+----------------+--------------+--------+
What I'm trying to get:
Dim stDate As Date
Dim nxDate As Date
Dim enDate As Date
Dim rate As Integer
stDate = "01/01/2016"
enDate = "31/12/2020"
rate = Me.initial_rate
Do While stDate < enDate
nxDate = DateAdd("yyyy", 1, stDate)
stDate = nxDate
rate = rate + 10
Debug.Print stDate, nxDate, rate
Loop
Output:
01/01/2018 01/01/2018 115
01/01/2019 01/01/2019 125
01/01/2020 01/01/2020 135
01/01/2021 01/01/2021 145
Any help would be appreciated.

Answer 1

You were close. You needed two extra temp dates to help you through the loop:
Dim stDate As Date
Dim nxstDate As Date
Dim nxenDate As Date
Dim nxyrDate As Date
Dim enDate As Date
Dim rate As Integer
stDate = "01/01/2016"
enDate = "31/12/2020"
rate = Me.initial_rate
nxyrDate = stDate
Do While nxyrDate < enDate
nxstDate = nxyrDate
nxyrDate = DateAdd("yyyy", 1, nxstDate)
nxenDate = DateAdd("d", -1, nxyrDate)
Debug.Print nxstDate, nxenDate, rate
rate = rate + 10
Loop
Output:
1/1/2016 12/31/2016 95
1/1/2017 12/31/2017 105
1/1/2018 12/31/2018 115
1/1/2019 12/31/2019 125
1/1/2020 12/31/2020 135
Hope that helps :)
** EDIT **
Additional code to answer request for placing results into a table:
First you need to create the table in your Access database
I called my table: tblIntervals_List
But you can call yours whatever you want, just change tblIntervals_List to your table name in the code below.
In Table tblIntervals_List you need three fields. You can name the fields whatever you want. But the first two fields must be of data type Date/Time and the third of data type Number.
Such as:
tblIntervals_List
Field Name Data Type
Interval_Start Date/Time
Interval_End Date/Time
Rate Number
Once you have created your table correctly, you can modify your code.
First You'll need to add another Dim statement for your SQL Insert Text:
Dim strSQLText As String
Then you'll need to turn off Warnings so you don't have to press the space bar after each record insert.
DoCmd.SetWarnings (WarningsOff)
Then in your loop, you need to create your SQL Insert code:
strSQLText = "INSERT INTO tblIntervals_List VALUES ('" & _
nxstDate & "', '" & _
nxenDate & "', " & _
rate & ") "
And run it with a Docmd statement:
DoCmd.RunSQL strSQLText
Then after the loop is finished, you need to reset your warnings on:
DoCmd.SetWarnings (WarningsOn)
And if you want, give your user a message box to let them know the query actually did something:
MsgBox "Records added to tblIntervals_List"
Plus, don't forget to comment out your Debug.Print
All of these steps are in the code below:
Dim stDate As Date
Dim nxstDate As Date
Dim nxenDate As Date
Dim nxyrDate As Date
Dim enDate As Date
Dim rate As Integer
Dim strSQLText As String
DoCmd.SetWarnings (WarningsOff)
stDate = "01/01/2016"
enDate = "31/12/2020"
rate = Me.initial_rate
nxyrDate = stDate
Do While nxyrDate < enDate
nxstDate = nxyrDate
nxyrDate = DateAdd("yyyy", 1, nxstDate)
nxenDate = DateAdd("d", -1, nxyrDate)
' Debug.Print nxstDate, nxenDate, rate
strSQLText = "INSERT INTO tblIntervals_List VALUES ('" & _
nxstDate & "', '" & _
nxenDate & "', " & _
rate & ") "
DoCmd.RunSQL strSQLText
rate = rate + 10
Loop
DoCmd.SetWarnings (WarningsOn)
MsgBox "Records added to tblIntervals_List"
And that code will add records to your Access table with your dates and rates.
Hope that helps :)

Answer 2

This is what I would do to make it easy for you to print out:
Dim stDate As Date
Dim nxDate As Date
Dim enDate As Date
Dim rate As Integer
Dim array_var As Variant
' additional variables
Dim coll_temp As Collection
Set coll_temp = New Collection
Dim array_temp(2) As Variant
' initialize initial variables
stDate = "01/01/2016"
nxDate = DateAdd("yyyy", 1, stDate)
nxDate = DateAdd("d", -1, nxDate)
enDate = "31/12/2020"
rate = 95 ' for you this would be Me.initial_rate
Do While stDate < enDate
' load array
array_temp(0) = stDate
array_temp(1) = nxDate
array_temp(2) = rate
' add to collection
coll_temp.Add Item:=array_temp
' increment dates
nxDate = DateAdd("yyyy", 1, nxDate)
stDate = DateAdd("yyyy", 1, stDate)
rate = rate + 10
Loop
To read this out this is the loop you need to do.
' print out each element in collection
For Each array_var In coll_temp
' print out each element in array
For int_element = 0 To UBound(array_temp)
' print the element
Debug.Print array_var(0); array_var(1); array_var(2)
Next int_element
Next
I hope this helps.