I have an Access form that queries items from a table. For example, if this is my table:
ID | Type | Active | Leading | DaysBehind
1 A Yes Yes 0
2 A Yes No 20
3 A Yes No 40
4 B Yes Yes 0
5 B Yes No 30
6 C Yes Yes 0
then a search (on my form) for Type=A returns:
txtID | cmbType | cmbActive | cmbLeading | txtDaysBehind
1 A Yes Yes 0
2 A Yes No 20
3 A Yes No 40
I want to write On Change VBA code, so that when I change ID 1 to Active=No, these things happen: ID 1 Leading=No and ID 2 Leading=Yes (because it's the fewest days behind).
Since ID 1 is my current record, this code is easy enough:
cmbLeading = "No"
I've written code that identifies ID 2 as the new leader.
rs = CurrentDB.OpenRecordset("SELECT ID FROM table WHERE Type='A' AND Active='Yes' ORDER BY DaysBehind")
How do I change the Leading value for ID 2? I've tried this:
CurrentDb.Execute "UPDATE table SET table.Leading='Yes' WHERE table.ID=2"
It isn't making any change to the table, and I'm guessing this is because I have the records open in the form. Do I need to make the change on the form? If so, how do I change a non-current record?
I finally figured this out. I needed to include a me.dirty=false to unlock the table. In particular, I put in if me.dirty then me.dirty=false.
Related
So I created a database table in MySQL that held permission rights for permissions and commands, the command rights started with the prefix command_ in the column permission_name and then I have an extra column called allowed_ranks, which is a list of INT rank ID's that are required, split by a , character.
The issue is, the command ones were anything higher, and I've put 1 id in allowed_ranks, is there a way I can loop through all the ones with column starting with command_ and change the allowed_ranks that are just 1 ID to every number starting from that to 9? 9 is the maximum rank ID.
I've already done part of the query, I'm just not sure how to do the updating?
UPDATE permission_rights` SET `allowed_ranks` = '?' WHERE `permission_name` LIKE 'command_%';
How would I update it to every number after the columns value up to 9? So lets say I had this record... just a quick example to ensure you know what I mean.
| permission_name | allowed_ids |
----------------------------------
| command_hello | 2
| command_junk | 5
| command_delete | 8
| command_update | 1
Would become...
| permission_name | allowed_ids |
----------------------------------
| command_hello | 2,3,4,5,6,7,8,9
| command_junk | 5,6,7,8,9
| command_delete | 8,9
| command_update | 1,2,3,4,5,6,7,8,9
The better approach would be to use a number generator (some method which will produce number from 1 to n), but general MySQL has no such capability.
If you use MariaDB you can use seq_1_to_1000 as suggested here in Answer by O.Jones.
However your use case seems to be simpler, since you said that the highest rank is 9, I would just use
update a
set a.allowed_ids = RIGHT('1,2,3,4,5,6,7,8,9',19-2*a.allowed_ids)
where a.permission_name like 'command_%'
For some reason, I am unable to export a table of subscribers from my phpList (ver. 3.0.6) admin pages. I've searched on the web, and several others have had this problem but no workarounds have been posted. As a workaround, I would like to query the mySQL database directly to retrieve a similar table of subscribers. But I need help with the SQL command. Note that I don't want to export or backup the mySQL database, I want to query it in the same way that the "export subscribers" button is supposed to do in the phpList admin pages.
In brief, I have two tables to query. The first table, user contains an ID and email for every subscriber. For example:
id | email
1 | e1#gmail.com
2 | e2#gmail.com
The second table, user_attribute contains a userid, attributeid, and value. Note in the example below that userid 1 has values for all three possible attributes, while userid's 2 and 3 are either missing one or more of the three attributeid's, or have blank values for some.
userid | attributeid | value
1 | 1 | 1
1 | 2 | 4
1 | 3 | 6
2 | 1 | 3
2 | 3 |
3 | 1 | 4
I would like to execute a SQL statement that would produce a row of output for each id/email that would look like this (using id 3 as an example):
id | email | attribute1 | attribute2 | attribute3
3 | e3#gmail.com | 4 | "" | "" |
Can someone suggest SQL query language that could accomplish this task?
A related query I would like to run is to find all id/email that do not have a value for attribute3. In the example above, this would be id's 2 and 3. Note that id 3 does not even have a blank value for attributeid3, it is simply missing.
Any help would be appreciated.
John
I know this is a very old post, but I just had to do the same thing. Here's the query I used. Note that you'll need to modify the query based on the custom attributes you have setup. You can see I had name, city and state as shown in the AS clauses below. You'll need to map those to the attribute id. Also, the state has a table of state names that I linked to. I excluded blacklisted (unsubscribed), more than 2 bounces and unconfirmed users.
SELECT
users.email,
(SELECT value
FROM `phplist_user_user_attribute` attrs
WHERE
attrs.userid = users.id and
attributeid=1
) AS name,
(SELECT value
FROM `phplist_user_user_attribute` attrs
WHERE
attrs.userid = users.id and
attributeid=3
) AS city,
(SELECT st.name
FROM `phplist_user_user_attribute` attrs
LEFT JOIN `phplist_listattr_state` st
ON attrs.value = st.id
WHERE
attrs.userid = users.id and
attributeid=4
) AS state
FROM
`phplist_user_user` users
WHERE
users.blacklisted=0 and
users.bouncecount<3 and
users.confirmed=1
;
I hope someone finds this helpful.
I have two related tables, results and userID.
results looks like this:
+----+--------+--------+
| ID | userID | result |
+----+--------+--------+
| 1 | abc | 124 |
| 2 | abc | 792 |
| 3 | def | 534 |
+----+--------+--------+
userID looks like this:
+----+--------+---------+
| id | userID | name |
+----+--------+---------+
| 1 | abc | Angela |
| 2 | def | Gerard |
| 3 | zxy | Enrico |
+----+--------+---------+
In results, the userID field is a lookup field; it stores userID.id but the combo box has userID.userID as its choices.
When I try to enter data into results by setting the userID combo box and entering a value for result, I get this error message:
You cannot add or change a record because a related record
is required in table `userID`.
This is strange, because I'm specifically selecting a value that's provided in the userID combo box.
Oddly, there are about 100 rows of data already in results with the same value for userID.
I thought this might be a database corruption issue, so i created a blank database and imported all the tables into it. But I still got the same error. What's going on here?
Both tables include a text field named LanID. You are using that field in this relationship, which enforces referential integrity:
The problem you're facing is due to the Lookup field properties. This is the Row Source:
SELECT [LanID].ID, [LanID].LanID FROM LanID ORDER BY [LanID];
But the value which gets stored (the Bound Column property) is the first column from that SELECT statement, which is the Long Integer [LanID].ID. So that number will not satisfy the relationship, which requires results.LanID = [LanID].LanID.
You must change the relationship or change the Lookup properties so both reference the same field value.
But if it were me, I would just eliminate the Lookup on the grounds that simple operations (such as this) become unnecessarily confusing when Lookup fields are involved. Make results.LanID a plain numeric or text field. If you want some kind of user-friendly drop-down for data entry, build a form with a combo or list box.
For additional arguments against Lookup fields, see The Evils of Lookup Fields in Tables.
If you are using a parameter query, make sure you have them in the same order as the table you are modifying and the query you have created. You might have one parameter inserting the conflicting data. Parameters are used in the order they are created...not the name of the parameter. I had the same problem and all I had to do was switch the order they were in so they matched the query. This is an old thread, so I hope this helps someone who is just now having this problem.
I have put a lot of effort into my database design, but I think I am
now realizing I made a major mistake.
Background: (Skip to 'Problem' if you don't need background.)
The DB supports a custom CMS layer for a website template. Users of the
template are limited to turning pages on and off, but not creating
their own 'new' pages. Further, many elements are non editable.
Therefore, if a page has a piece of text I want them to be able to edit,
I would have 'manually' assigned a static ID to it:
<h2><%= CMS.getDataItemByID(123456) %></h2>
Note: The scripting language is not relevant to this question, but the design forces
each table to have unique column names. Hence the convention of 'TableNameSingular_id'
for the primary key etc.
The scripting language would do a lookup on these tables to find the string.
mysql> SELECT * FROM CMSData WHERE CMSData_data_id = 123456;
+------------+-----------------+-----------------------------+
| CMSData_id | CMSData_data_id | CMSData_CMSDataType_type_id |
+------------+-----------------+-----------------------------+
| 1 | 123456 | 1 |
+------------+-----------------+-----------------------------+
mysql> SELECT * FROM CMSDataTypes WHERE CMSDataType_type_id = 1;
+----------------+---------------------+-----------------------+------------------------+
| CMSDataType_id | CMSDataType_type_id | CMSDataType_type_name | CMSDataType_table_name |
+----------------+---------------------+-----------------------+------------------------+
| 1 | 1 | String | CMSStrings |
+----------------+---------------------+-----------------------+------------------------+
mysql> SELECT * FROM CMSStrings WHERE CMSString_CMSData_data_id=123456;
+--------------+---------------------------+----------------------------------+
| CMSString_id | CMSString_CMSData_data_id | CMSString_string |
+--------------+--------------------------------------------------------------+
| 1 | 123456 | The answer to the universe is 42.|
+--------------+---------------------------+----------------------------------+
The rendered text would then be:
<h2>The answer to the universe is 42.</h2>
This works great for 'static' elements, such as the example above. I used the exact same
method for other data types such as file specifications, EMail Addresses, Dates, etc.
However, it fails for when I want to allow the User to dynamically generate content.
For example, there is an 'Events' page and they will be dynamically created by the
User by clicking 'Add Event' or 'Delete Event'.
An Event table will use keys to reference other tables with the following data items:
Data Item: Table:
--------------------------------------------------
Date CMSDates
Title CMSStrings (As show above)
Description CMSTexts (MySQL TEXT data type.)
--------------------------------------------------
Problem:
That means, each time an Event is created, I need to create the
following rows in the CMSData table;
+------------+-----------------+-----------------------------+
| CMSData_id | CMSData_data_id | CMSData_CMSDataType_type_id |
+------------+-----------------+-----------------------------+
| x | y | 6 | (Event)
| x+1 | y+1 | 5 | (Date)
| x+2 | y+2 | 1 | (Title)
| x+3 | y+3 | 3 | (Description)
+------------+-----------------+-----------------------------+
But, there is the problem. In MySQL, you can have only 1 AUTO INCREMENT field.
If I query for the highest value of CMSData_data_id and just add 1 to it, there
is a chance there is a race condition, and someone else grabs it first.
How is this issue typically resolved - or avoided in the first place?
Thanks,
Eric
The id should be meaningless, except to be unique. Your design should work no matter if the block of 4 ids is contiguous or not.
Redesign your implementation to add the parts separately, not as a block of 4. Doing so should simplify things overall, and improve your scalability.
What about locking the table before writing into it? This way, when you are inserting a row in the CMSData table, you can get the last id.
Other suggestion would be to not have an incremented id, but a unique generated one, like a guid or so.
Lock Tables
I have a scenario where I need to insert the data into table temporarily and later on approval or confirmation, make it permanent. The data will be inserted by a user and approval or denial needs to be done by Super User.
What I think of now is to have two different but identical tables (temporary and main) and the user will insert the data into temp table. After confirmation of Super User, the data will be moved to main table. But the problem comes when a database contains very large number of tables then this process will become more complex.
EDIT : This implies to CREATE EDIT & DELETE commands.
Is there any simpler or better approach of doing this?
Please suggest.
Using a version table (related to comment):
The idea here is to have a version table; when your user changes a piece of information the new version is stored in this table along with the related ID.
Then all you need to do is join on the PersonID and select the most recent accepted version.
This means the user can make as many updates as they want but they won't show until the super user accepts them, it also means the data is never destroyed (stored in the version table) and they don't need to implement rollback as it's already there!
See: http://sqlfiddle.com/#!3/cc77f/4
People Table:
ID | Age Etc... (Info That Doesn't Change)
-----------------------
1 | 12
2 | 16
3 | 11
People Version Table:
VersionID | PersonID | Name | Approved
-----------------------
1 | 1 | Stevz | FALSE
2 | 1 | Steve | TRUE
3 | 2 | James | TRUE
4 | 3 | Jghn | FALSE
5 | 3 | John | TRUE
Example table SQL
CREATE TABLE People
(
id int identity primary key,
age int
);
CREATE TABLE PeopleVersion
(
versionId int identity primary key,
peopleId int,
name varchar(30),
approved varchar(30)
);
Example Query
SELECT * FROM People p
INNER JOIN PeopleVersion v ON p.id = v.peopleID
WHERE v.approved = 'TRUE'
ORDER BY versionId DESC
A further insight:
You could even have three states of Approved; null meaning no admin has chosen yet, TRUE meaning it was accepted and FALSE meaning it was rejected
You could show the user the most recent from null and true, show the admin all three and show the other users of the site only versions that were true
Old Comments
Could you just add a field called approved to the table and then hide anything without the approval flag set to TRUE?
It could default to FALSE and only the super user would be able to see items with the flag set to FALSE
E.g.
Name | Age | Approved
-----------------------
Steve | 12 | FALSE
James | 16 | TRUE
John | 11 | FALSE
The user would only see James, but the SuperUser would see all three listed
Alternatively using your temporary and main tables is the other way of looking at this problem, though this may lead to problems as everything get's larger
The easiest approach is a flag within the table marking an entry either approved or not-yet approved.
Then just change the retrieving logic to only show entries where that flag is set to approved.