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

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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).


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