vb.net - How update a SQL table from a modified datatable? -

-

i used dataset designer create ftwdataset holds alarmtext table sqlexpress database. far form contains datagridview1. code below shows contents of alarmtext table plus 1 added checkbox column (which populate display-only data, , not issue here).

    dim ta new ftwdatasettableadapters.alarmtexttableadapter     dim dt new ftwdataset.alarmtextdatatable     ta.fill(dt)     datagridview1.datasource = dt      'create new bool column in datatable     dt.columns.add("newcol", (new boolean).gettype)

what else need use datagridview edit , save values in alarmtext table?

here's brief msdn walkthrough on topic.

some notes:

  • you shouldn't need binding source persist changes database.
  • to make table adapter accessible other procedures in form, make form-scoped (a.k.a. member) variable instead of method-scoped, in example.
  • if created dataset using dataset designer, , you're fetching original data more simple table or view, adapter won't know how update in original database. have manually configure update command in situation. reference, see tableadapter update commands section in above link.

i should mention avoid tableadapters in ado.net plague. in theory they're convenient , powerful. in practice, many of them (especially 1 oracle provider) buggy, , if don't work right you're totally screwed.

if you're pulling 1 underlying table, adapter should work fine (so ignore nihilistic advice time being). may adding additional column in code breaks adapter (since there's no corresponding column in database table).


Comments

Post a Comment

Popular posts from this blog

java - netbeans "Please wait - classpath scanning in progress..." -

-
when try compile netbeans projects message/error : "please wait - classpath scanning in progress..." and nothing happens , have have wait enternity conmpile "hello world"... now first thing have moved new office building, laptop same. it's secure enviroment lot of "security", can't connect anywhere almost. have changed user dir in netbeans.conf save data in c:\program files\user any ideas how fix this? alrady tried reinstalling netbeans, changing save location between standart , newone... just ideas find problem look @ cpu - netbeans busy (100% on 1 core) or blocking (95% idle)? standard, ant or maven build? libraries , use absolute or relative paths? start simple "hello world" project (no dependencies), add 1 lib (log4j or similiar), located in project folder , - if works - move lib other locations (choose locations similiar libs on real classpath) there chance, don't have access rights folders/shares conta...
Read more

python - Scipy curvefit RuntimeError:Optimal parameters not found: Number of calls to function has reached maxfev = 1000 -

-
Image
i want make logharitmic fit. keep getting runtime error: optimal parameters not found: number of calls function has reached maxfev = 1000 i use following script. can tell me go wrong? use spyder still beginner. import math import matplotlib mpl scipy.optimize import curve_fit import numpy np #data f1=[735.0,696.0,690.0,683.0,680.0,678.0,679.0,675.0,671.0,669.0,668.0,664.0,664.0] t1=[1,90000.0,178200.0,421200.0,505800.0,592200.0,768600.0,1036800.0,1371600.0,1630800.0,1715400.0,2345400.0,2409012.0] f1n=np.array(f1) t1n=np.array(t1) plt.plot(t1,f1,'ro',label="original data") # curvefit def func(t,a,b): return a+b*np.log(t) t=np.linspace(0,3600*24*28,13) popt, pcov = curve_fit(func, t, f1n, maxfev=1000) plt.plot(t, func(t, *popt), label="fitted curve") plt.legend(loc='upper left') plt.show() your original data t1 , f1 . therefore curve_fit should given t1 second argument, not t . popt, pcov = curve_fit(func,...
Read more

java - where to store the user credentials in an enterprise application(EAI)? -

-
Image
background/context we developing event notification service . application @ high level looks below: our developene scope involves widget , ens. " ens " acts central point of collection types of events of interest users. user wants know when these types of events occur registers ens, identifies events in order , matches notifications subscriptions. the user wants subscibe should valid user of intergrated application(db, sap system etc) the sequence of events: now question is: what best pracitces in storing users db, sap etc credentials. edit how should user authenticated? should everytime messages delivered?(as @duffymo mentioned, if use strategy, affect source system) additional info: ens web-services. ens polls sap(and other applications) , problem becoming more complex. in sap there data-level authorization. not users allowed see events/data. if sap has pushed data, along user info has authorized see, no issues @ all. case 1: scheduler init...
Read more