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developer:scriptsamples:recordsets [2015/09/14] (current)
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 +======Using Disconnected Recordset for Sorting Data======
 +> **Developer:​** //​[[developer:​rhinoscript|RhinoScript]]//​
 +> **Summary:​** //​Demonstrates using a disconnected recordset ​ to sort data.//
  
 +=====Overview=====
 +If you are dealing with data which requires more than just key-value pairs and fits best in 2-D array, and you wanted to perform sorting and filtering on it, then **Disconnected Recordsets** will be an excellent option. ​
 +
 +A disconnected recordset is essentially a database that exists only in memory; it is not tied to a physical database. You create the recordset, add records to it, and then manipulate the data, just like any other recordset. The only difference is that the moment the script terminates, the recordset, which is stored only in memory, disappears as well.
 +
 +To use a disconnected recordset to sort data, you must first create the recordset, adding any fields needed to store the data. After you have created the fields, you then use the **AddNew** method to add new records to the recordset, using the same process used to add new records to a physical database. After the recordset has been populated, a single line of code can then **Sort** the data on the specified field or fields.
 +
 +=====Example=====
 +The following example demonstrates how to sort an array of 3-D points in ascending x, y, z order. The code can be quickly modified to sort the point in any order by simply modifying the **Sort** statement.
 +
 +<code vb>
 +Sub SortPoints
 +
 +  ' Local constants
 +  Const adDouble = 5 
 +
 +  ' Local variables
 +  Dim arrPoints, arrPoint, x, y, z
 +  Dim objRecordSet
 +
 +  ' Get the coordinates of selected point objects
 +  arrPoints = Rhino.GetPointCoordinates
 +  If IsNull(arrPoints) Then Exit Sub
 +
 +  ' Create a disconnected recordset object
 +  Set objRecordSet = CreateObject("​ADODB.Recordset"​)
 +
 +  ' Define the fields of the recordset
 +  Call objRecordSet.Fields.Append("​X",​ adDouble)
 +  Call objRecordSet.Fields.Append("​Y",​ adDouble)
 +  Call objRecordSet.Fields.Append("​Z",​ adDouble)
 +
 +  ' Open the recordset
 +  objRecordSet.Open
 +
 +  ' Add the curve data to the recordset
 +  For Each arrPoint In arrPoints
 +    objRecordSet.AddNew ​
 +    objRecordSet("​X"​).Value = arrPoint(0)
 +    objRecordSet("​Y"​).Value = arrPoint(1)
 +    objRecordSet("​Z"​).Value = arrPoint(2)
 +    objRecordSet.Update ​
 +  Next
 +
 +  ' Sort the recordset by x,y,z in ascending order
 +  objRecordSet.Sort = "X ASC, Y ASC, Z ASC"
 +
 +  ' Iterate through the sorted recordset and print each record'​s values
 +  objRecordSet.MoveFirst
 +  Do Until objRecordSet.EOF
 +    x = objRecordSet("​X"​).Value
 +    y = objRecordSet("​Y"​).Value
 +    z = objRecordSet("​Z"​).Value
 +    Call Rhino.Print(Rhino.Pt2Str(Array(x,​ y, z)))
 +    objRecordSet.MoveNext
 +  Loop
 +
 +  objRecordSet.Close
 +  ​
 +End Sub
 +</​code>​
 +
 +=====More Information=====
 +  * [[http://​msdn.microsoft.com/​en-us/​library/​windows/​desktop/​ms681510(v=vs.85).aspx|Recordset Object (ADO)]]
 +  * [[http://​technet.microsoft.com/​en-us/​magazine/​2008.09.heyscriptingguy.aspx?​pr=PuzzleAnswer|Use a disconnected recordset to sort large data sets in VBScript]].
 +  * [[http://​blogs.technet.com/​b/​heyscriptingguy/​archive/​2006/​10/​11/​how-can-i-delete-a-record-from-a-disconnected-recordset.aspx|How Can I Delete a Record From a Disconnected Recordset?​]]
 +
 +\\
 +
 +{{tag>​Developer RhinoScript}}
developer/scriptsamples/recordsets.txt ยท Last modified: 2015/09/14 (external edit)