I am beginner to MySQL, so my question is: when create a new column in a specific table, is there any way to write regular expression to detect accepted value before inserting?
the main Idea from question is to add domain name column and I need to check if user entry matching my requirements before accept the value to store in database.
I hope my question cleared.
note: I cant use PHP or any front end language, it's necessary to do that in mysql database
thanks a lot in advance.
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I am trying to write an Microsoft Access query from a form with a multi value field being the criteria. The field I am trying to use is called Population and the field is represented in my database as a List Box that allows multiple values and it is in the Building table. The values it allows are the following:
"Singles";"Familes";"Families with Children";"Youth/Young Adults";"Veterans";
The form that I am creating is called HousingSearch.
I am trying to create a form which uses this field, so someone could use the list box and check off the values they want and click on the button which would open a query. I know having done this with single value fields the criteria in the query looks something like
[forms]![HousingSearch]![Building]![Population]
but if you try the same thing for a multi value field nothing is returned for the query. Any help would be appreciated.
From the information you have provided it seems that the phrase [Forms]![HousingSearch]![Building]![Population] are combining a request that starts with a form and then jumps to a table.
You are asking access to find data in a form but the information you're most likely trying to access is in a table. I don't quite understand what you're end result is but I think that you most likely want to refer to your information this way [Building]![Population]. Referring to your data this way makes access look at the table of [Building] and then into the field of [Population].
It's been a while since you posted, if you haven't cleared things up already I hope this helps.
just facing a little problem right now.
I have a layout-table that contains one field pages. This should specify for which pages the layout should be applied.
The possible contents are "closed" ranges like '3-5' or open ranges like '3-*'. But it should also be possible to add single pages.
So is there a good way to accomplish a content like that
'3-5;11;15;17-*'
in a single field?
Or do you know better ways?
Is there a possibility to query this field like
SELECT * WHERE IN_RANGE(pages, '5') (Pseudo-Code)
I want to prevent creating a table page because it would contain nothing else and also don't want to do the validation in php.
I am happy to provide more information if necessary.
This is a tricky question i dont see "native" sql option for this.
My first idea was to store information about pages as varchar and implement method to tokenize that string so youll have values which you can then process by sql query.
When using ActiveRecord, if you are updating a record, it only adds the fields that have changed to the query. I need a way to tell it to always add a particular field to my query, even if Rails doesn't think it changed. In my example, I always want to set a field to "U" when saving a record. The name of the field is DELETE_FLAG. So, I want to see DELETE_FLAG="U" in the UPDATE query that is sent to MySQL every time.
I've tried DELETE_FLAG_will_change! In the model, but that doesn't seem to have done anything, perhaps because I put it in the wrong place?
I've seen the touch method as well, but this will not do. I don't want to update the record again afterwards.
This seems so basic, I'm sure I must be overlooking something here. Any help would be appreciated. Thanks!
Is it possible to run a trigger whenever a new row is inserted into lets say shipping_rate, and it will check column company within that row for a certain string. If that certain string is is there, I then want to perform an equation on column cost to change the current number. Is this feasible in MySQL?
Yes, it is entirely possible as trigger can do essentially anything to the database that a normal query could. You can read up on how to do that in official manual.
I'm recieving the following error on trying to run an append query in access.
Microsoft Office Access set .... and it didnt't add... 779280 records(s) due to validation rule violations.
If I choose to run the query anyways, nothing actually happens.
To give some context, I'm simply trying to copy a populated field, consisting of values similar to "16-2009-02, 34-2010-02, et cetera" to another currently unpopulated field.
The fields themselves have no set validation rules, and both have the standard text field options.
I'm hoping to be able to simply remove those hyphens, and fix the issue. But I guess that's what I'm not sure about, are those hyphens actually a problem?
Running SP3 w/ Access 2003.
Thanks in advance!
Does the destination field have Allow Zero Length set to false or Required set to true? If it does, it is possible that some of the data from the source column is null or is set to an empty string. In addition, you should verify that the field sizes on the new column is equal to larger than the source column.
EDIT On appending from one table to another, you must ensure that you populate the columns that makeup the primary key of the destination table. Thus, from your screenshot, you need to include the loggerid and datetime columns from the "Log ID" table. Now, if there are collisions, Access should tell you how many rows generated collisions and let you append the ones that did not collide with the uniqueness restriction on loggerid and datetime
Make sure the target column is not indexed or, if it is, that duplicates are allowed. Access often makes indexing decisions on your behalf and sometimes they are not correct.