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Help with Data Tablesbaby steps. I'm rewriting something I did initially in PHP / MySql on a vb.net / mysql platform. Here's what I'm doing: 1) Data is pulled from the internet and stored to a CSV file 2) Data is loaded into the database with some changes 3) All sorts of data crunching goes on. Step one works fine -- data is saved to a csv file. Step 2 -- The data is loaded from a CSV file into a table in a dataset. This part works fine too. I have added a column to the table once it is full. Code is: DS.Tables("CSV").Columns.Add("Symbol") That works fine too. Now I want to set fill that "Symbol" column with something of my choosing. This will change regularly. How do I do this? I have poked around the web for quite some time. I tried using: Dim TestCmd As New OleDb.OleDbCommand("UPDATE CSV Set Symbol = 'YHOO';") ' testing below DA.SelectCommand = TestCmd DS.AcceptChanges() And that doesn't work at all. Of course I"m very new to ADO.Net and could use some pointers here. The only tutorials I can find online are how to create a table from scratch. I want to simply add a column and, if possible, set the text in all the fields in this column. Eventually, I will need to know how to take the info from this datatable and dump it into my database, but that's for later. Please help! Thanks. -Scott I guess, on a funamental level, how do I run a standard query against a
datatable in a dataset? Scott,
The dataset has some methods to do what you want. It is the DataTable.Select and the inbuild view the DefaultView. You can make more DefaultViews and than the name becomes DataView. There comes something new in version 9.0 what looks like a kind of logical but free structured query language. The name of that is Linq. You probably have seen that name already I hope this helps, Cor Show quoteHide quote "Scott" <scott@scott.scott> schreef in bericht news:Ds-dnexiLs3KeoHZnZ2dnUVZ_vednZ2d@comcast.com... >I guess, on a funamental level, how do I run a standard query against a >datatable in a dataset? > Scott,
A dataset is not a database it is a from a Class instanced Object which is very much based on OOP. The DataSet is a collection from Relations and DataTables A DataTable is a collection from DataColumns and DataRows (The DataColumns descrive the items) A DataRow exist from a collection of items. You can inherit the dataset to give all the parts strongly typed names and types. Therefore the first item in the first datatable in the first dataset is ds.table(0).rows(0).item(0) 'be aware that in this not strongly typed format is object I hope this gives an idea Cor Show quoteHide quote "Scott" <scott@scott.scott> schreef in bericht news:jqGdnUlQjIhTe4HZnZ2dnUVZ_u2dnZ2d@comcast.com... > Ok. Brand new at this so please give a little patience and help me on the > baby steps. I'm rewriting something I did initially in PHP / MySql on a > vb.net / mysql platform. Here's what I'm doing: > > 1) Data is pulled from the internet and stored to a CSV file > 2) Data is loaded into the database with some changes > 3) All sorts of data crunching goes on. > > Step one works fine -- data is saved to a csv file. > Step 2 -- The data is loaded from a CSV file into a table in a dataset. > This part works fine too. I have added a column to the table once it is > full. Code is: > DS.Tables("CSV").Columns.Add("Symbol") > > That works fine too. Now I want to set fill that "Symbol" column with > something of my choosing. This will change regularly. How do I do this? > I have poked around the web for quite some time. I tried using: > > > > Dim TestCmd As New OleDb.OleDbCommand("UPDATE CSV Set Symbol = 'YHOO';") > > ' testing below > > DA.SelectCommand = TestCmd > > DS.AcceptChanges() > > > > And that doesn't work at all. Of course I"m very new to ADO.Net and could > use some pointers here. The only tutorials I can find online are how to > create a table from scratch. I want to simply add a column and, if > possible, set the text in all the fields in this column. Eventually, I > will need to know how to take the info from this datatable and dump it > into my database, but that's for later. > > > > Please help! Thanks. > > > > -Scott > > That helped. Seems datatables weren't what I was hoping. I just created a
quick loop to fill in the cells for the recently created column. Now my goal is to take this info and dump it into a mySql table that may or may not have duplicates. Film at 11. Thanks. Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message news:%23Nu2Z5xSGHA.5884@TK2MSFTNGP14.phx.gbl... > Scott, > > A dataset is not a database it is a from a Class instanced Object which is > very much based on OOP. > > The DataSet is a collection from Relations and DataTables > A DataTable is a collection from DataColumns and DataRows (The DataColumns > descrive the items) > A DataRow exist from a collection of items. > You can inherit the dataset to give all the parts strongly typed names and > types. > > Therefore the first item in the first datatable in the first dataset is > > ds.table(0).rows(0).item(0) 'be aware that in this not strongly typed > format is object > > I hope this gives an idea > > Cor > > > "Scott" <scott@scott.scott> schreef in bericht > news:jqGdnUlQjIhTe4HZnZ2dnUVZ_u2dnZ2d@comcast.com... >> Ok. Brand new at this so please give a little patience and help me on >> the baby steps. I'm rewriting something I did initially in PHP / MySql >> on a vb.net / mysql platform. Here's what I'm doing: >> >> 1) Data is pulled from the internet and stored to a CSV file >> 2) Data is loaded into the database with some changes >> 3) All sorts of data crunching goes on. >> >> Step one works fine -- data is saved to a csv file. >> Step 2 -- The data is loaded from a CSV file into a table in a dataset. >> This part works fine too. I have added a column to the table once it is >> full. Code is: >> DS.Tables("CSV").Columns.Add("Symbol") >> >> That works fine too. Now I want to set fill that "Symbol" column with >> something of my choosing. This will change regularly. How do I do this? >> I have poked around the web for quite some time. I tried using: >> >> >> >> Dim TestCmd As New OleDb.OleDbCommand("UPDATE CSV Set Symbol = 'YHOO';") >> >> ' testing below >> >> DA.SelectCommand = TestCmd >> >> DS.AcceptChanges() >> >> >> >> And that doesn't work at all. Of course I"m very new to ADO.Net and >> could use some pointers here. The only tutorials I can find online are >> how to create a table from scratch. I want to simply add a column and, >> if possible, set the text in all the fields in this column. Eventually, >> I will need to know how to take the info from this datatable and dump it >> into my database, but that's for later. >> >> >> >> Please help! Thanks. >> >> >> >> -Scott >> >> > > 
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