I have an problem, i am using simple query to select from column (VARCHAR), what user searched and appending +1 string to it from database.
For example if i had in table following values (title):
My name is SOMEONE.
Have a great day.
It's possible.
Mouse on the way.
My mouse is on other way.
Is there any mouse?
And user wants to retreive the keyword mouse.
I wish to output him following from the values above:
Mouse on
mouse is
mouse?
Also if the user types Mouse on it should return
Mouse on the and so on, appending one string from database to found ones (if any).
I could do it outside of database, but i need after retreiving string DISTINCT values with Limitation.
For now i used SUBSTRING_INDEX(title , ' ', ".$totalWords.")
where $totalWords were the user sent to my programme.
Problem with my query was when you type other it will find and return:
My mouse but that's not what i want, i want to it output from found string +1 append so it would be other way
If i wasn't so clear i will give my best to explain it better.
Thank you.
You could use LOCATE(substr,str) 1 to locate the position of the first occurence of the user input. afterwards use SUBSTRING(str FROM pos) 2 to get a substring starting at the position of the first occurence of the user input and finally use your SUBSTRING_INDEX(title , ' ', ".$totalWords.") to get the second word.
PS: Sounds like an autocompletion feature? probably there are better ways to do it than with a relational database
Related
forgive me for shoddy coding/description of the problem. I'm new to programming and this is my first question!
Anyways, I am building a simple inventory system with tkinter while using mySQL as a database. Currently, I am working on a feature that would allow a user to pick a department using an Optionmenu and then get all the items in that department. I have the items listed in one table and the departments listed in another with a FOREIGN KEY connecting the items table to the primary key (department_string) in the departments table.
My goal is to have mySQL deliver a list of departments and then to have the Optionmenu use that list for it's options. I then need to query the database with the department selected in the Optionmenu to find all the items in that department. My problem is that variable.get() from the Optionmenu returns parentheses and commas that is first received when I query the database the first time. This makes it so I cannot directly input the variable.get() into the string in the cursor. Here is the code:
department_cursor.execute("SELECT department_string FROM departments")
department_list = department_cursor.fetchall()
variable = StringVar(search_window)
variable.set(department_list[0])
user_entry = OptionMenu(search_window, variable, *department_list)
***
cursor_b.execute("SELECT item WHERE department_string = " + "'" + str(variable.get()) + "'")
I believe the problem is that variable.get() provides the special characters like the parentheses and comma that came from the original mySQL query. For example if the departments are HR, Warehouse, R&D then mySQL returns [('HR',), ('Warehouse',), ('R&D',)] this is then fed into the Option menu which then variable.get() spits out something like ('HR',), and so mySQL doesn't recognize this.
So far the only things I can think of is to use a for loop to delete all the special characters in what the Optionmenu returns or to hard code what the string for each department should be. Both seem suboptimal and although I'm pretty new to programming I think it's a little too much like rube goldberg machine.
Anyways, if you made it this far, thank you so much for reading this! Once again, I'm brand new to all of this so any help you can give me is greatly appreciated!
.get() is going to return whatever is in the optionmenu. If the values you put into the optionmenu have the undesirable characters, the value you get out will too.
The database call is going to return a list (rows) of lists (columns), and it doesn't look like you're taking that into account.
Here is my story:
I'm writting a script that permits to see every users in an array of group (I mean, you select 2 group, it show every users in one of these two groups). It also do some other treatment. But it's OK for this part.
Everything seems to work correcly. Except for only one user.
The idea is, I have to get the e-mail of a user, to then compare users'e-mail got in a former group, to see if this user is (or not) already listed ( in order to avoid duplicate).
The user (this one only) won't use my function. I supposed it was a group, but it really is a user.. I'm pretty sure it is an option to select ( or not) in the user's preference, but which one?
PS: here is the error quote
TypeError: Fonction getEmail introuvable dans l'objet
(TypeError: getEmail function not found in object)
And here is the code I use in order to get e-mails:
for(var i in objuser){
for(var j in objuser[i])
{
objuser[i][j]=objuser[i][j].getEmail();
}
}
Objuser is a list of User Object. First dimension (I) is the group, second dimension (j), is users of the "I" group.
PROBLEM NOT SOLVED:
the reason:
I have 2 functions that do treatments. Theses Two function need an array, that another function create (which is long to execute). My code is done in such a way, if i execute consecutively these 2 treatment functions with the same array, the second to be played use an incorrect array.
So i clone it with :
var groupsUser2 = JSON.parse(JSON.stringify(groupsUser));
but, now that i dont use anymore email adresses ( i mean String), but direct Users (i mean Object), the former code don't clone correctly:
array1 : user's array (Objects)
array2 = JSON.parse(JSON.stringify(array1))
log(array1) :[blabla1#...com,blabla2#...com,blabla3#...com, .....]
log(array2) :[{},{},{}………]
SO.... Here is the new question: Is there a simple way to copy an Object's array ?
Here is the former question: What rights configuration unallow me to use the getEmail() function for a specific contact?
I need an answer just for one of these two questions, and i'll be able to correct my problem. Any idea guys???????
never use "for x in array" its bad use of javascript on an array because the array has the "length" property which is a number and not the object your loop expects.
instead use " for (i=0;...." or forEach.
Well, I was using getEmail() function in order to compare users got in one group, to others got in another group , so that i can avoid duplicates.
I was checking with IndexOf() if the user adress were in the array of the other group's users.
I don't know why , but now it works even if i don't get the e-mail of the user. So , the problem that was happening for one user can't happen anymore.
Conclusion: Problem solved. Thx mates
I thought about a solution: try .. catch, so that the email which won't be get, will be potentially duplicated because I will not be able to find the user if already displayed or not without his e-mail, but at least the script will not crash.
I have a nested repeated structure, the repeated structure is of variable length. For example, it could be a person object with a repeated structure that holds cities the person has lived in. I'd like to find the last item in that list say to find current city person lives in. Is there an easy way to do this, I tried looking around jsonpath functions but I'm not sure how to use it with "within". Any help please?
1) You can use LAST and WITHIN
SELECT
FIRST(cell.value) within record ,
LAST(cell.value) within record
FROM [publicdata:samples.trigrams]
where ngram = "! ! That"
2) or if you want something more advanced you can use POSITION
POSITION(field) - Returns the one-based, sequential position of field within a set of repeated fields.
You can check the samples from trigrams (click on Details to see the unflatten schema)
https://bigquery.cloud.google.com/table/publicdata:samples.trigrams?pli=1
And when you run POSITION, you get the ordering of that field.
SELECT
ngram,
cell.value,
position(cell.volume_count) as pos,
FROM [publicdata:samples.trigrams]
where ngram = "! ! That"
Now that you have the position, you can query for last one.
I am creating a program in VB.NET which uses an online MySQL database to retrieve certain data. I have now succeeded in connecting and getting some basic stuff out of it. Now, what I want to do is that when an user presses a button it has to update the list. What happens is that the stuff that is already in the database also gets resent and so the list just doubles himself, although it adds the new database value.
How can I make sure that it only adds new values to the list, instead of adding all values from the list again? I have read that you can use the Preserve keyword with arrays, though this isn't an array and neither have I figured out how to convert my data into an array.
Private Sub generateList()
DB.writeQuery("SELECT snacks.ID, snacks.naam, snacks.baktijd FROM snacks")
While DB.DR.Read
ListBox1.Items.Add(DB.DR.Item("naam"))
End While
DB.closeConnection()
End Sub
This is the piece of code I use to generate the list, I reuse this code to refresh the list. As you can see, it uses my own written MySQL class. I know it makes an connection so there is nothing wrong with that.
Any help would be appreciated.
What you will want to do is to clear the ListBox before you reload the list. You can do this like so:
ListBox1.Items.Clear()
Then when you reload the list, the items will not be duplicated.
Looks like you need to clear your listbox before adding the items.
ListBox1.Items.Clear()
Try this my friend:
If Not listBox1.Items.Contains(DB.DR.Item("naam")) Then
ListBox1.Items.Add(DB.DR.Item("naam"))
else
'this item already exists.
end if
Each parameter in a URL can have multiple values. How can I separate them? Here's an example:
http://www.example.com/search?queries=cars,phones
So I want to search for 2 different things: cars and phones (this is just a contrived example). The problem is the separator, a comma. A user could enter a comma in the search form as part of their query and then this would get screwed up. I could have 2 separate URL parameters:
http://www.example.com/login?name1=harry&name2=bob
There's no real problem there, in fact I think this is how URLs were designed to handle this situation. But I can't use it in my particular situation. Requires a separate long post to say why... I need to simply separate the values.
My question is basically, is there a URL encodable character or value that can't possibly be entered in a form (textarea or input) which I can use as a separator? Like a null character? Or a non-visible character?
UPDATE: thank you all for your very quick responses. I should've listed the same parameter name example too, but order matters in my case so that wasn't an option either. We solved this by using a %00 URL encoded character (UTF-8 \u0000) as a value separator.
The standard approach to this is to use the same key name twice.
http://www.example.com/search?queries=cars&queries=phones
Most form libraries will allow you to access it as an array automatically. (If you are using PHP (and making use of $_POST/GET and not reinventing the wheel) you will need to change the name to queries[].)
You can give them each the same parameter name.
http://www.example.com/search?query=cars&query=phones
The average server side HTTP API is able to obtain them as an array. As per your question history, you're using JSP/Servlet, so you can use HttpServletRequest#getParameterValues() for this.
String[] queries = request.getParameterValues("query");
Just URL-encode the user input so that their commas become %2C.
Come up with your own separator that is unlikely to get entered in a query. Two underscores '__' for example.
Why not just do something like "||"? Anyone who types that into a search area probably fell asleep on their keyboard :} Then just explode it on the backend.
easiest thing to do would be to use a custom separator like [!!ValSep!!].