Extracting SQLite database into text fields from specific row - database

I am trying to connect to a SQLite database and have a method that specifies a specific row from the database (the first column in the database is “ID” and is a primary key) then extract the information from a few other columns in that row and display them in text fields.
This will be used for a simple Trivia game I am making; I will later make a random method that will choose the row at random.
I have been struggling with this problem for several weeks and I have been through loads of tutorials but all of them deal with displaying the data in a table view, I want to display it simply on text fields in a View based app. I am fairly confused at this point so any help starting from loading the database to displaying the data in the text fields would be GREATLY APPRECIATED!
Thanks!

Link to libsqlite3.dylib (and import <sqlite3.h>) to access the power of SQLite. There are a number of lightweight Objective-C front ends and I suggest you pick one. In this example, I use fmdb (https://github.com/ccgus/fmdb) to read the names of people out of a previously created database:
NSString* docsdir = [NSSearchPathForDirectoriesInDomains(
NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSString* dbpath = [docsdir stringByAppendingPathComponent:#"people.db"];
FMDatabase* db = [FMDatabase databaseWithPath:dbpath];
if (![db open]) {
NSLog(#"Ooops");
return;
}
FMResultSet *rs = [db executeQuery:#"select * from people"];
while ([rs next]) {
NSLog(#"%# %#",
[rs stringForColumn:#"firstname"],
[rs stringForColumn:#"lastname"]);
}
[db close];
/* output:
Snidely Whiplash
Dudley Doright
*/
That illustrates talking to the database; knowing SQL is up to you (and is a different topic). You can include a previously constructed SQLite file in your app bundle, but you can't write to it there; the solution is to copy it from your app bundle into another location, such as the Documents directory, before you start working with it.
Finally, to put strings into text fields (UITextField), set their text property. So for example instead of the while loop shown above, where I log the database results, I could use those results to set text field values:
myTextField.text = [rs stringForColumn:#"firstname"];
myOtherTextField.text = [rs stringForColumn:#"lastname"];

Related

How to find a MoveTo destination filled by database?

I could need some help with a Anylogic Model.
Model (short): Manufacturing scenario with orders move in a individual route. The workplaces (WP) are dynamical created by simulation start. Their names, quantity and other parameters are stored in a database (excel Import). Also the orders are created according to an import. The Agent population "order" has a collection routing which contains the Workplaces it has to stop in the specific order.
Target: I want a moveTo block in main which finds the next destination of the agent order.
Problem and solution paths:
I set the destination Type to agent and in the Agent field I typed a function agent.getDestination(). This function is in order which returns the next entry of the collection WP destinationName = routing.get(i). With this I get a Datatype error (while run not compiling). I quess it's because the database does not save the entrys as WP Type but only String.
Is there a possiblity to create a collection with agents from an Excel?
After this I tried to use the same getDestination as String an so find via findFirst the WP matching the returned name and return it as WP. WP targetWP = findFirst(wps, w->w.name == destinationName);
Of corse wps (the population of Workplaces) couldn't be found.
How can I search the population?
Maybe with an Agentlink?
I think it is not that difficult but can't find an answer or a solution. As you can tell I'm a beginner... Hope the description is good an someone can help me or give me a hint :)
Thanks
Is there a possiblity to create a collection with agents from an Excel?
Not directly using the collection's properties and, as you've seen, you can't have database (DB) column types which are agent types.1
But this is relatively simple to do directly via Java code (and you can use the Insert Database Query wizard to construct the skeleton code for you).
After this I tried to use the same getDestination as String an so find via findFirst the WP matching the returned name and return it as WP
Yes, this is one approach. If your order details are in Excel/the database, they are presumably referring to workplaces via some String ID (which will be a parameter of the workplace agents you've created from a separate Excel worksheet/database table). You need to use the Java equals method to compare strings though, not == (which is for comparing numbers or whether two objects are the same object).
I want a moveTo block in main which finds the next destination of the agent order
So the general overall solution is
Create a population of Workplace agents (let's say called workplaces in Main) from the DB, each with a String parameter id or similar mapped from a DB column.
Create a population of Order agents (let's say called orders in Main) from the DB and then, in their on-startup action, set up their collection of workplace IDs (type ArrayList, element class String; let's say called workplaceIDsList) using data from another DB table.
Order probably also needs a working variable storing the next index in the list that it needs to go to (so let's say an int variable nextWorkplaceIndex which starts at 0).
Write a function in Main called getWorkplaceByID that has a single String argument id and returns a Workplace. This gets the workplace from the population that matches the ID; a one-line way similar to yours is findFirst(workplaces, w -> w.id.equals(id)).
The MoveTo block (which I presume is in Main) needs to move the Order to an agent defined by getWorkplaceByID(agent.workplaceIDsList.get(nextWorkplaceIndex++)). (The ++ bit increments the index after evaluating the expression so it is ready for the next workplace to go to.)
For populating the collection, you'd have two tables, something like the below (assuming using strings as IDs for workplaces and orders):
orders table: columns for parameters of your orders (including some String id column) other than the workplace-list. (Create one Order agent per row.)
order_workplaces table: columns order_id, sequence_num and workplace_id (so with multiple rows specifying the sequence of workplace IDs for an order ID).
In the On startup action of Order, set up the skeleton query code via the Insert Database Query wizard as below (where we want to loop through all rows for this order's ID and do something --- we'll change the skeleton code to add entries to the collection instead of just printing stuff via traceln like the skeleton code does).
Then we edit the skeleton code to look like the below. (Note we add an orderBy clause to the initial query so we ensure we get the rows in ascending sequence number order.)
List<Tuple> rows = selectFrom(order_workplaces)
.where(order_workplaces.order_id.eq(id))
.orderBy(order_workplaces.sequence_num.asc())
.list();
for (Tuple row : rows) {
workplaceIDsList.add(row.get(order_workplaces.workplace_id));
}
1 The AnyLogic database is a normal relational database --- HSQLDB in fact --- and databases only understand their own specific data types like VARCHAR, with AnyLogic and the libraries it uses translating these to Java types like String. In the user interface, AnyLogic makes it look like you set the column types as int, String, etc. but these are really the Java types that the columns' contents will ultimately be translated into.
AnyLogic does support columns which have option list types (and the special Code type column for columns containing executable Java code) but these are special cases using special logic under the covers to translate the column data (which is ultimately still a string of characters) into the appropriate option list instance or (for Code columns) into compiled-on-the-fly-and-then-executed Java).
Welcome to Stack Overflow :) To create a Population via Excel Import you have to create a method and call Code like this. You also need an empty Population.
int n = excelFile.getLastRowNum(YOUR_SHEET_NAME);
for(int i = FIRST_ROW; i <= n; i++){
String name = excelFile.getCellStringValue(YOUR_SHEET_NAME, i, 1);
double SEC_PARAMETER_TO_READ= excelFile.getCellNumericValue(YOUR_SHEET_NAME, i, 2);
WP workplace = add_wps(name, SEC_PARAMETER_TO_READ);
}
Now if you want to get a workplace by name, you have to create a method similar to your try.
Functionbody:
WP workplaceToFind = wps.findFirst(w -> w.name.equals(destinationName));
if(workplaceToFind != null){
//do what ever you want
}

SQL - trying to find a set of data which only has a certain set of values but not anything else in a few columns

Hopefully an easy problem for an experienced SQL person. I have an application which uses SQL Server, and I cannot perform this query in the application, so I'm hoping to back-door it, but I need help.
I have a table with a large list of emails and all its metadata. I'm trying to find email that is only between parties of this one company and flag them.
What I did was search where companyName.com is in To and From and marked a TagField as 1 (I did this through my application's front end).
Now what I need to do is search where any other possible values, ignoring companyName.com exist in To and From where I've already flagged them as 1 in TagField. From will usually just have one value, but To could have multiple, all formatted differently, but all separated by a semi-colon (I will probably have to apply this same search to CC and BCC columns, too).
Any thoughts?
Replace the ; with the empty string. Then check to see if the length changed. If there's one email address, there shouldn't be a ';'. You could also use the same technique to replace the company name with the empty string. Anything left would be the other companies.
select email_id, to_email
from yourtable
where TagField = 1 and len(to_email) <> len(replace(to_email,';',''))
This solution is based on the following thread
Number of times a particular character appears in a string
So I went an entirely different route and exported my data to a CSV and used Python to get to where I needed. Here's the code I used in case anybody needs it. What this returned for me was a list of DocIDs (unique identifiers that were in the CSV) where ever there was an email address in the To field that wasn't from one specific domain. I went into the original CSV and made sure all instances of this domain name were in all lowercase, too.
import csv
import tkinter as tk
from tkinter import filedialog
root = tk.Tk()
root.withdraw()
file_path = filedialog.askopenfilename()
sub = "domainname"
def findMultipleTo(dict):
for row in reader:
if row['To'].find(";") != -1:
toArray = row['To'].split(';')
newTo = [s for s in toArray if sub not in s]
row['To'] = newTo
else:
row['To'] = 'empty'
with open('location\\newCSV-BCCFieldSearch.csv', 'a') as f:
if row['To'] != "empty" and row['To'] != []:
print(row['DocID'], row['To'], file = f)
else:
pass
with open(file_path) as csvfile:
reader = csv.DictReader(csvfile)
findMultipleTo(reader)

Syncronizing data between two django servers

I have a central Django server containing all of my information in a database. I want to have a second Django server that contains a subset of that information in a second database. I need a bulletproof way to selectively sync data between the two.
The secondary Django will need to pull its subset of data from the primary at certain times. The subset will have to be filtered by certain fields.
The secondary Django will have to occasionally push its data to the primary.
Ideally, the two-way sync would keep the most recently modified objects for each model.
I was thinking something along the lines of having using TimeStampedModel (from django-extensions) or adding my own DateTimeField(auto_now=True) so that every object stores its last modified time. Then, maybe a mechanism to dump the data from one DB and load it in to the other such that only the more recently modified objects are kept.
Possibilities I am considering are django's dumpdata, django-extensions dumpscript, django-test-utils makefixture or maybe django-fixture magic. There's a lot to think about, so I'm not sure which road to proceed down.
Here is my solution, which fits all of my requirements:
Implement natural keys and unique constraints on all models
Allows for a unique way to refer to each object without using primary key IDs
Sublcass each model from TimeStampedModel in django-extensions
Adds automatically updated created and modified fields
Create a Django management command for exporting, which filters a subset of data and serializes it with natural keys
baz = Baz.objects.filter(foo=bar)
yaz = Yaz.objects.filter(foo=bar)
objects = [baz, yaz]
flat_objects = list(itertools.chain.from_iterable(objects))
data = serializers.serialize("json", flat_objects, indent=3, use_natural_keys=True)
print(data)
Create a Django management command for importing, which reads in the serialized file and iterates through the objects as follows:
If the object does not exist in the database (by natural key), create it
If the object exists, check the modified timestamps
If the imported object is newer, update the fields
If the imported object is older, do not update (but print a warning)
Code sample:
# Open the file
with open(args[0]) as data_file:
json_str = data_file.read()
# Deserialize and iterate
for obj in serializers.deserialize("json", json_str, indent=3, use_natural_keys=True):
# Get model info
model_class = obj.object.__class__
natural_key = obj.object.natural_key()
manager = model_class._default_manager
# Delete PK value
obj.object.pk = None
try:
# Get the existing object
existing_obj = model_class.objects.get_by_natural_key(*natural_key)
# Check the timestamps
date_existing = existing_obj.modified
date_imported = obj.object.modified
if date_imported > date_existing:
# Update fields
for field in obj.object._meta.fields:
if field.editable and not field.primary_key:
imported_val = getattr(obj.object, field.name)
existing_val = getattr(existing_obj, field.name)
if existing_val != imported_val:
setattr(existing_obj, field.name, imported_val)
except ObjectDoesNotExist:
obj.save()
The workflow for this is to first call python manage.py exportTool > data.json, then on another django instance (or the same), call python manage.py importTool data.json.

Trigger Duplicate CSV

am trying to upload a CSV file / insert a bulk of records using the import wizard. In short I would like to keep the latest record, in case if duplicates are found. Duplicates record are a combination of First name, Last name and title
For example if my CSV file looks like the following:
James,Wistler,34,New York,Married
James,Wistler,34,London,Married
....
....
James,Wistler,34,New York,Divorced
This should only keep in my org: James,Wistler,34,New York,Divorced
I have been trying to write a trigger before an update / insert but so far no success Here is my trigger code: (The code is not yet finished (only filering with Firstname), I am having a problem deleting found duplicate in my CSV ) Any hints. Thanks for reading!
trigger CheckDuplicateInsert on Customer__c(before insert,before update){
Map <String, Customer__c> customerFirstName = new Map<String,Customer__c>();
list <Customer__c> CustomerList = Trigger.new;
for (Customer__c newCustomer : CustomerList)
{
if ((newCustomer.First_Name__c != null) && System.Trigger.isInsert )
{
if (customerFirstName.containsKey(newCustomer.First_Name__c) )
//remove the duplicate from the map
customerFirstName.remove(newCustomer.First_Name__c);
//end of the if clause
// add this stage we dont have any duplicate, so lets add a new customer
customerFirstName.put(newCustomer.First_Name__c , newCustomer);
}
else if ((System.Trigger.oldMap.get(newCustomer.id)!= null)&&newCustomer.First_Name__c !=System.Trigger.oldMap.get(newCustomer.id).First_Name__c )
{//field is being updated, lets mark it with UPDATED for tracking
newCustomer.First_Name__c=newCustomer.First_Name__c+'UPDATED';
customerFirstName.put(newCustomer.First_Name__c , newCustomer);
}
}
for (Customer__c customer : [SELECT First_Name__c FROM Customer__c WHERE First_Name__c IN :customerFirstName.KeySet()])
{
if (customer.First_Name__c!=null)
{
Customer__c newCustomer=customerFirstName.get(customer.First_Name__c);
newCustomer.First_Name__c=Customer.First_Name__c+'EXIST_DB';
}
}
}
Purely non-SF solution would be to sort them & deduplicate in Excel for example ;)
Good news - you don't need a trigger. Bad news - you might have to ditch the import wizard and start using Data Loader. The solution is pretty long and looks scary but once you get the hang of it it should start to make more sense and be easier to maintain in future than writing code.
You can download the Data Loader in setup area of your Production org and here's some basic info about the tool.
Anyway.
I'd make a new text field on your Contact, call it "unique key" or something and mark it as External Id. If you have never used ext. ids - Jeff Douglas has a good post about them.
You might have to populate the field on your existing data before proceeding. Easiest would be to export all Contacts where it's blank (from a report for example), fill it in with some Excel formulas and import back.
If you want, you can even write a workflow rule to handle the generation of the unique key. This might help you when Mrs. Jane Doe gets married and becomes Jane Bloggs and also will make previous point easier (you'd just import Contacts without changes, just "touching" them and the workflow will fire). Something like
condition: ISBLANK(Unique_key__c) || ISCHANGED(FirstName) || ISCHANGED(LastName) || ISCHANGED(Title)
new value: Title + FirstName + ' ' + LastName
Almost there. Fire Data Loader and prepare an upsert job (because we want to insert some records and when duplicate is found - update them instead).
My only concern is what happens when what's effectively same row will appear more than once in 1 "batch" of records sent to SF like in your example. Upsert will not know which value is valid (it's like setting x = 7; and x = 5; in same save to DB) and will decide to fail these rows. So you might have to tweak the amount of records in a batch in Data Loader's settings.

When writing to an SQLite file in AppleScript 2.2 with application Database Events

I am making an AppleScript application with AppleScript 2.2 on Mac OS X 10.7 (Build: 11A511) Lion. What my application is doing is capturing the current iTunes song and storing it if the song is different from the last one. Then I told it to take the the current song and place it into an SQLite file using Database Events. Basically it is adding the current song to a new field, but when the song changes it says that there are no old fields and then writes the song (the process repeats...); I do have a save after it makes the field.
My code is as follows:
if currentsong is not equal to previous_song then
tell application "Database Events"
tell database "songlist"
set song to make new record with properties {name:"songs"}
set song_count to count fields
tell song
make new field with properties {name:currentsong, value:song_count + 1}
end tell
end tell
save database "songlist"
end tell
end if
It seems you're a little confused by records and fields. A database has records and a record has fields. In your code you are telling the database to count the fields... which is a problem because a database has records, not fields.
So change "fields" to "records" where you set the song_count. Also, if you want that count to be correct then put that line ahead of where you create the new record because you're trying to get the count before you add a new record.

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