+----- Code.fmp12 ------+
tables
...
Users
Doctors
Lens Info
Drugs
Diagnosis Codes
...
Equipment *** (Manufacturer, Model Number, Com Port, Speed, Bytes, Bits, ...
Installed (yes/no). 1 record for each piece of equipment we support. )
...
+----------------------+
+----Exam.fmp12 --------+
tables
...
Exam *** (Eye exam data for a patient. Multiple exams per patient)
...
+----------------------+
I am working with a Medical Records / Office Management system for eye doctors, optometrists. We provide our solution to multiple customers across the country. One of the things our software does is transfer data from equipment that is attached to a computer to a patient's exam record so the doctors and staff don't have to enter it manually. Currently, I manually modify the scripts that make the data transfer happen. I would like to set up a table containing all the information for each manufacturer and piece of equipment and have the customer select which piece of equipment they have installed and use the data from these fields in the script so I don't have to modify them manually.
In the script I need to know which data from the "Equipment" table to use to set up and transfer the data from the equipment to the exam record but I don't need data about the equipment stored in the exam record. I hope this makes sense.
My question is, how can my script acquire that data from the fields in the "Equipment" table without creating a relationship between the "Exam" table and "Equipment" table? Is it possible? If not, what would be a good way to make this possible.
My background is not databases, so I still struggle with this aspect of databases.
Thanks for all your help!
You can fetch any data with the ExecuteSQL function from anywhere. That's your best option. You may also get what you need using a value list from the Equipment table and use the ValueListItems function in the script.
One of the most valuable tool in FileMaker is the ExecuteSQL() function, but the support documentation is not very good, this is by far the best guide you can find for learning or creating SQL queries in FileMaker.
Here is the way I manage my ExecuteSQL() calls, this will prevent the function from breaking if you ever rename a field or table, you just need to search and add the custom function: GetTableNameSQL()
Let (
[
~qry = "
SELECT a. <<fieldTableA>>
FROM <<tableA>> a
" ;
~SQL =
ExecuteSQL (
Substitute (
~qry ;
[ "<<tableA>>" ; GetTableNameSQL ( TABLE::field ; 1 ) ] ;
[ "<<fieldTableA>>" ; GetFieldNameSQL ( TABLE::field ; 1 ) ]
) ; "" ; ""
)
] ;
~SQL
)
Related
While using Power BI for a few months now, we (the user group) encountered an issue that is not really clear to us.
We use Power-BI with a remote SQL-Server data source, we access the data source through direct query.
Let's pretend we have 2 Tables as below-
Table name: Issue
Column:
ResolutionTime(Date/Time)
IssueID(Unique Numbers)
Table Name: WorkItem
Column:
start (Date/Time)
end (Date/Time)
IssueID (Unique Numbers, Foreign Key to "Issue" table)
Table WorkItem also contain a calculated column "WorkTime" which uses this DAX-expression as below-
WorkTime = WorkItem[end] - WorkItem[start]
The two tables are configured through Power-Bi having a two-way 1:n relationship that can be queried to collect all "WorkItem"(s) assigned to an "Issue" entry, using the "IssueID" as correlation column.
To be able to compute the aggregated "work-time" for each "WorkItem", we use a new/calculated table with the following DAX expression to aggregate the total amount of time invested for a single "Issue":
SumWork =
SUMMARIZE(
WorkItem, WorkItem[IssueID], "All work per item", SUM(WorkItem[WorkTime])
)
The above table computes the total invested work-time for a particular issue, grouping/summarizing results based on the "IssueID" foreign key. This new calculated table is also configured to have a relationship with the "Issue" table, this time a "1:1" relationship, using the IssueID as correlation column.
Now to compute the time that the issue was worked on + the time for Resolution should be summarized in a calculated column inside "Issue", but this does not work:
ResolutionAndWorkTime = Issue[ResolutionTime] + SumWork["All work per item"]
But the above DAX expression fails to compile, as it always reports that it returns "more than one result", thus not being a singular result. But that is suprising, as the two table ("Issue" and "SumWork" are related to each other with a "1:1" relationship).
Tables:
Issues
IssueID ResolutionTime ResolutionAndWorkTime
1 03:20:20 ???
2 01:20:20 ???
3 00:20:20 ???
WorkItem
IssueID start end WorkTime
1 1-2-2020 3:20:20 1-2-2020 3:25:20 00:05:00
1 2-2-2020 6:20:20 2-2-2020 7:20:20 01:00:00
3 1-3-2020 3:20:20 1-3-2020 3:29:20 00:09:00
Any ideas what to look for? Data-types? Table-definition? Table-relationships? We checked other Stackoverflow questions/answers, but no good ideas retrieved so far.
NOTE that a lot of join/merge features of Power BI are not available if direct-query is used and thus joining the tables is not really an option (we think).
You need this following code for your new Calculated column.
Visit HERE To know more about RELATED.
ResolutionAndWorkTime = Issues[ResolutionTime] + RELATED(SumWork[All work per item])
Based on input provided by "mkRabbani" (see other answer) we investigated why "RELATED" does not function as expected. The problem originates in the access to the database. As suspected earlier the function delivers the expected results once the database access is switched to "import" instead of "direct-query".
As a workaround we now joins the data inside the SQL server by using traditional database views. Of course this only works for scenarios where the database is under control of the data analytics team.
I need to choose best approach between two approaches that I can follow.
I have a Flutter app that use sqflite to save data, inside the database I have two tables:
Employee:
+-------------+-----------------+------+
| employee_id | employee_name |dep_id|
+-------------+-----------------+------+
| e12 | Ada Lovelace | dep1 |
+-------------+-----------------+------+
| e22 | Albert Einstein | dep2 |
+-------------+-----------------+------+
| e82 | Grace Hopper | dep3 |
+-------------+-----------------+------+
SQL:
CREATE TABLE Employee(
employee_id TEXT NOT NULL PRIMARY KEY,
employee_name TEXT NOT NULL ,
dep_id TEXT,
FOREIGN KEY(dep_id) REFERENCES Department(dep_id)
ON DELETE SET NULL
);
Department:
+--------+-----------+-------+
| dep_id | dep_title |dep_num|
+--------+-----------+-------+
| dep1 | Math | dep1 |
+--------+-----------+-------+
| dep2 | Physics | dep2 |
+--------+-----------+-------+
| dep3 | Computer | dep3 |
+--------+-----------+-------+
SQL:
CREATE TABLE Department(
dep_id TEXT NOT NULL PRIMARY KEY,
dep_title TEXT NOT NULL ,
dep_num INTEGER,
);
I need to show a ListGrid of departments that are stored in the Employee table. I should look at Employee table and fetch department id from it, This is easy but after fetching that dep_id I need to make a card from those ids so I need information from Department table.
complete inforamtion for thoses id I had fetched from Emplyee table is inside Department table.
There are thousands of rows in each table.
I have a database helper class to connect to the database :
DbHelper is something like this:
Future<List<String>> getDepartmentIds() async{
'fetch all dep_id from Employee table'
}
Future<Department> getDepartment(String id) async{
'fetch Department from Department table for a specific id'
}
Future<List<Department>> getEmployeeDepartments() async{
'''1.fetch all dep_id from Employee table
2.for each id fetch Department records from Department table'''
var ids = await getDepartmentIds();
List<Departments> deps=[];
ids.forEach((map) async {
deps.add(await getDepartment(map['dep_id']));
});
}
There is two approaches:
First One:
Define a function in dbhelper that returns all dep_id from Employee table(getDepartmentIds and another function that returns a department object(model) for that specific id.(getDepartment)
Now I need two FutureBuilder inside each other, one for fetching ids and the other one for fetching department model.
second One:
Define a function that first fetch ids then inside that function each id is maped to department model.(getEmployeeDepartments)
So I need one FutureBuilder .
Which one is better??
should I let FutureBuilders handle it or I should put pressure on dbHelper to habdle it?
If I use the first approach then I have to(as far as I can imagine!) put the the second future call(the one that fetch Department Object(model) based on it's id(getDepartment)) on build function and it's recommended no to do so.
And the problem with second one is that it does a lot of nested call in dbHelper.
I used ListView.builder for performance.
I checked both with some data but couldn't figure out which one is better. I guess it depends both on flutter and sqlite(sqflite).
which one is better or is there any better approach?
Given that I don't see too much code on this example, I'll do a high-level answer on your questions.
Evaluate Approach One
Right off the bat this part sticks out: "returns all dep_id from Employee table"
I would say scratch that, since "return all" is typically never a good solution, especially since you mention your tables have a lot of rows.
Evaluate Approach Two
I'm not sure what the difference in performance this has compared to the first approach, seems also bad for the same reasons. I think this one just changes your UI logic a big is all.
Typical 'Endless' List Approach
You would do a query on the Employees table with a join to the Departments table.
You would implement Pagination on your UI and pass in your values to the query from step one.
At a basic level you'll need these variables: Take, Skip, HasMore
Take: The count # of items to request each query
Skip: The count # of items to skip on the next query, this will be the size of the number of items you currently have in your List in memory driving your UI.
HasMore: You can set this on the response of each query, to let the UI know if there are still more items or not.
As you scroll down the list, when you get to the bottom, you will request more items .
Initially issue a query for example: Take: 10, Skip: 0
Next query when you hit the bottom of the UI: Take: 10, Skip: 10
etc..
Example sql query:
SELECT *
FROM Employees E
JOIN Departments D on D.id = E.dept_id
order by E.employee_name
offset {SKIP#} rows
FETCH NEXT {TAKE#} rows only
Hopefully, this helps, I'm not fully sure what you're trying to do actually - in terms of Code.
As far as I can tell, what you're looking to do is get a list of employees with relevant info including department.
If that's the case, then it's tailor made for INNER JOIN. Something like this:
SELECT Employee.*, Department.dep_id, Department.dep_title
FROM Employee INNER JOIN Department
ON Employee.dep_id = Department.dep_id;
(although you may want to double check that, my SQL is a bit rusty).
This would do what you need in one step. However, there is still the issue of what you're asking which seems to be "Is it more efficient to do many small requests or one big one, and what are the performance ramifications".
The answer to that is a bit specific to Flutter. What's happening when you do a request with SQFLITE, is that it is processing whatever you've passed to it, sending it to java/objc and possibly doing more processing and pushes processing to a backround thread, which then calls to the SQLITE library which does more processing to understand the request, then actually reads the data on the disk to do the operation, then returns back to the java/objc layer, which pushes the response to the UI thread, which in turns responds back to dart.
If that doesn't sound particularly efficient, that's because it isn't =D. If you're doing this a few times (or even a few hundred) it's probably fine, but if you're getting into thousands as you state it might start slowing down.
The alternative you've proposed is to do one large request. You will know better than I whether that is wise; if it's a couple thousand but only ever a couple thousand, and the data you're returning is always going to be relatively small (i.e. just a 10-20 character name and department name), then you'll have say (20+20)*2000 = 8000b = 80kb of data. Even if you assume the overhead will double that size, 160 kb of data shouldn't be enough to faze any relatively recent smartphone (after all that's much smaller than any single photo!).
Now, taking some domain specific knowledge, you could optimize this. For example, if you know the number of departments is much smaller than employees (i.e. < 100 or something), you could skip the entire issue of doing joins, and simply request all departments before this begins and put it in a map (dep_id => dep_title), and then once you've requested employees you could just simply do that lookup from dep_id to dep_title yourself. That way your requests wouldn't have to include the dep_title over and over again.
That being said, you may want to consider paging the employee lookup whether or not you use a join. You'd do this by requesting 100 employees (or whatever number) at a time rather than the entire batch - that way you don't have the overhead of 1000+ calls through the stack, but you also don't have a large block of data all in memory all at once.
SELECT * FROM Employee
WHERE employee_name >= LastValue
ORDER BY employee_name
LIMIT 100;
Unfortunately that doesn't fit in as well with how flutter does lists, so you'd probably need to have something like a 'EmployeeDatabaseManager' that does the actual requests, and your list would call into it to get the data. That's probably beyond the scope of this question though.
I've only had a (frustrating) couple days experience with SQL Server, and I need some help, since I cant find anything related to my question when searching.
For background info, I'm working in an accountancy, and right now I'm trying to create a table for balance statements to use in crystal reports. Each invoice has multiple items, but for the statement I need to sum them all up with the invoice reference being the information that links the group of data that needs to be summarised.
So, what I need is to pull information from one table (dbo.SalesInvItems), this information including the date (InvDate), the due date (InvDueDate), and the customer name (CustomerName). This information stays the same with the Invoice Reference (InvRef), and it's what I want to use to link the two tables.
For example, Invoice Reference: 1478 will always have the date 14/05/18, the due date: 14/06/18 and the customer name: Pen Sellers Ltd.
The same Invoice Reference is used by multiple rows, but the only thing that changes (that I need) is the Invoice Item Total (InvItemTotal).
For example, the one reference will always be addressed to Pen Sellers, but one item has the Total as £13 and another item using the same reference is £20.
The Invoice Item Total is what I need to sum up. I want to add all the Invoice Item Total's together that have the same Invoice Reference, while joining the tables.
Sales Invoices
So when I've inserted the references into the table (sorry they're not the same in both pictures, I was having problems making examples and I made a mistake), I want to grab the information from the Invoice table to fill it in, going from this...
Pre Solution
To this...
Desired Result
The desired location is a table called dbo.Statement.
1.Is this even possible to do?
2.How would I go about doing this?
3.Is there a method I could use that would make sure that every time I insert an Invoice Reference into the Statement table, it would automatically pull out the data needed from the Invoice Table?
If any additional information is needed, just say and I'll do my best to provide it, I have never asked a question on here before and I'm new to SQL Server and coding in general.
Im using SQL Server Management Tool 2017
Thank You
Select item.InvRef
, item.CustomerName
, item.InvDate
, item.InvDueDate
, Sum(item.InvItemTotal) InvAmt
, sum(IsNull(payments.Amount,0)) PayAmount
, Sum(item.InvItemTotal) InvAmt - sum(IsNull(payments.Amount,0)) as Balance
from SalesInvItems item
left join payments -- you didn't define this
on item.InvRef = payments.InvRef
group by item.InvRef
, item.CustomerName
, item.InvDate
, item.InvDueDate
Select item.InvRef
, item.CustomerName
, item.InvDate
, item.InvDueDate
, Sum(item.InvItemTotal) InvAmt
from SalesInvItems item
left join Statement
on item.InvRef = Statement.Reference
group by item.InvRef
, item.CustomerName
, item.InvDate
, item.InvDueDate
Trying to figure out how to change a structure from what I currently have which is this:
tblHaulLogs
intLogID
intHaulType
intSerial
intOriginSource
intOrigin
intDestinationSource
intDestination
dtmHaulDate
ccyLogPay
intHauler
txtLogNotes
intInvoiceID
In this table, what I am doing is using the origin and destination source fields to determine which table the fk for the origin and destination comes from. This feels very wrong to me.
tblHaulTypes
intHaulTypeID
chrHaulType
intOriginSourceType
intDestinationSourceType
Data in the Haul Types Table:
LOT, 1, 1
DEL, 1, 2
RPO, 2, 1
Now let me explain:
The first type happens when an item goes from a sales lot to another sales lot.
The second type happens when an item goes from a sales lot to a customer(sale gets delivered).
The third type happens when an item returns from the customer back to the sales lot.
Then the Item can be resold/returned/resold/returned(rent-to-own system).
Now, here are the problems I have:
An Haul Log's origin will always be the destination of the last move. Therefore I thought that the origin field is redundant. However, it's the relation between the destination of the last move and the destination of the new move that defines what the shipper gets paid and what type of haul it is.
In other words, even though the first type and the third type technically have the same fields, the type of move is not the same because of the previous move type. What do I need to do here? Am I totally missing the boat on what the structure should be?
The questions I need to answer based on this data is:
How many Items do I have on my sales lots that are new inventory(have never been sold).
How many Items do I have that have been sold and returned(doesn't matter how many times).
I'm guessing at the relationship between the various fields and tables.
Your tblHaulTypes table looks fine.
intHaulTypeID
chrHaulType
intOriginSourceType
intDestinationSourceType
You're missing a haul type that accounts for deliveries from suppliers to your lots.
There has to be some table that lists your lots. I'd call it tblHaulLot.
intLotNumber
txtLotName
...
I'd make a tblHaulTransaction table that looks like this.
intTransactionID
intHaulTypeID
intHauler
intOriginOrganizationID
intDestinationOrganizationID
intOriginLot (null if origin is supplier)
intDestinationLot (null if destination is customer)
dtmHaulDate
txtLogNotes
Now, we need an tblOrganization.
intOrganizationID
txtOrganizationName
txtOrganizationAddress
...
The organization at ID 0 is your organization. Suppliers and customers would fill the rest of the table.
I'd make a tblHaulInvoice table that looks like this.
intInvoiceID
intTransactionID
ccyTransactionPay
dtmDateInvoiced
AmountInvoiced
The amount invoiced (and amount paid) have to be accounted for in some table. I don't know what ccy stands for, and I don't know your 3 letter code for a decimal (money) field.
How many Items do I have on my sales lots that are new inventory(have never been sold). How many Items do I have that have been sold and returned(doesn't matter how many times).
Nowhere in your data model is there any kind of inventory table. I'd need to know a lot more about your business to create one or more inventory tables.
I was wondering if there's any contradiction or futur problems against a table in a database which contains about 80 columns. There will be only VARCHARs, few INT and maybe 1 or 2 MESSAGE. I did some research on the net but there's nothing really talking about that kind of problem...In other terms, is this okay or even 'normal' to put that much of values inside a table??
Thanks in advance!
You shouldn't have any real problems if the fields are mostly integers. Most DBMSes have a limit on row length, so a bunch of long columns can cause issues...but unless the varchar columns are very long, you're probably OK.
I've honestly never even needed to think about that, though -- with a properly normalized database, it's quite rare to ever need that many columns in a table.
More columns you have, more memory server needs to process the records.
I recomend to use the "multiple to one" relation scheme in this case.
Example of tables:
customer
id
name
email
...
ins_app_form (Insurance application form)
id
customer_id (relation with customer)
date
... (here comes some other data if you need)
ins_app_item (Insurance application form items/fields)
id
ins_app_form_id (relation with Insurance application form)
question (the name of a question in application form)
answer (customer's answer)
So to show the application form with this scheme you will need to run a query:
SELECT
iaf.id AS application_id,
iaf.date AS `date`,
iai.question,
iai.answer
FROM ins_app_form AS iaf
LEFT JOIN ins_app_item AS iai ON iai.ins_app_form_id=iaf.id
WHERE iaf.customer_id=<ID of a customer>
This query will bring you something like this:
id date question answer
1 2014-03-31 "Year" "2008"
1 2014-03-31 "Car make" "Audi"
1 2014-03-31 "Car model" "Q7"
...