Can I create an index on a DataTable ?
On the following DataTable, I would like to create index on "Price", can I
do that ?
Thank you.
Dim DT As New DataTable
DT.Columns.Add("Price", GetType(System.Int32))
DT.Columns.Add("ID", GetType(System.Int32))
DT.Columns.Add("Vol", GetType(System.Int32))
Dim r As DataRow = DT.NewRow
r.Item(0) = 99
r.Item(1) = 1234
r.Item(2) = 350
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 98
r.Item(1) = 1233
r.Item(2) = 300
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 97
r.Item(1) = 1230
r.Item(2) = 375
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 96
r.Item(1) = 1231
r.Item(2) = 250
r.Item(3) = 1
DT.Rows.Add(r)
DT.AcceptChanges()
3  4877 
fniles,
No, I don't believe you can add an index to a datatable.
Keep in mind that datasets/datatables are not the same as an in-memory sql
database and trying to treat them as such will only lead to frustration.
Having said that, if you need an index for performance while selecting, you
might look into the dataview and its find methods. It will index on whatever
you set as its sort column.
Kerry Moorman
"fniles" wrote:
Can I create an index on a DataTable ?
On the following DataTable, I would like to create index on "Price", can I
do that ?
Thank you.
Dim DT As New DataTable
DT.Columns.Add("Price", GetType(System.Int32))
DT.Columns.Add("ID", GetType(System.Int32))
DT.Columns.Add("Vol", GetType(System.Int32))
Dim r As DataRow = DT.NewRow
r.Item(0) = 99
r.Item(1) = 1234
r.Item(2) = 350
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 98
r.Item(1) = 1233
r.Item(2) = 300
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 97
r.Item(1) = 1230
r.Item(2) = 375
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 96
r.Item(1) = 1231
r.Item(2) = 250
r.Item(3) = 1
DT.Rows.Add(r)
DT.AcceptChanges()
On Sep 18, 8:41*am, "fniles" <fni...@pfmail.comwrote:
Can I create an index on a DataTable ?
On the following DataTable, I would like to create index on "Price", can I
do that ?
Thank you.
Dim DT As New DataTable
DT.Columns.Add("Price", GetType(System.Int32))
DT.Columns.Add("ID", GetType(System.Int32))
DT.Columns.Add("Vol", GetType(System.Int32))
Dim r As DataRow = DT.NewRow
r.Item(0) = 99
r.Item(1) = 1234
r.Item(2) = 350
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 98
r.Item(1) = 1233
r.Item(2) = 300
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 97
r.Item(1) = 1230
r.Item(2) = 375
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 96
r.Item(1) = 1231
r.Item(2) = 250
r.Item(3) = 1
DT.Rows.Add(r)
DT.AcceptChanges()
Not really. One exception is the PK which is indexed.
Thank you
How can you create PK on the dataTable ?
"Brian Gideon" <br*********@yahoo.comwrote in message
news:b1**********************************@b38g2000 prf.googlegroups.com...
On Sep 18, 8:41 am, "fniles" <fni...@pfmail.comwrote:
Can I create an index on a DataTable ?
On the following DataTable, I would like to create index on "Price", can I
do that ?
Thank you.
Dim DT As New DataTable
DT.Columns.Add("Price", GetType(System.Int32))
DT.Columns.Add("ID", GetType(System.Int32))
DT.Columns.Add("Vol", GetType(System.Int32))
Dim r As DataRow = DT.NewRow
r.Item(0) = 99
r.Item(1) = 1234
r.Item(2) = 350
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 98
r.Item(1) = 1233
r.Item(2) = 300
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 97
r.Item(1) = 1230
r.Item(2) = 375
r.Item(3) = 1
DT.Rows.Add(r)
r = DT.NewRow
r.Item(0) = 96
r.Item(1) = 1231
r.Item(2) = 250
r.Item(3) = 1
DT.Rows.Add(r)
DT.AcceptChanges()
Not really. One exception is the PK which is indexed. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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