In PowerShell how to troubleshoot exception in DataSet.Fill? - powershell

Question

I'm using a function I found on SO to retrieve data from SQL server and generate XML.
function Invoke-SQL {
param(
[string] $sqlCommand = $(throw "Please specify a query.")
)
$connectionString = "Data Source=$server;Initial Catalog=$database;user id=$uid;password=$pwd"
$connection = new-object system.data.SqlClient.SQLConnection($connectionString)
$command = new-object system.data.sqlclient.sqlcommand($sqlCommand,$connection)
$connection.Open()
$adapter = New-Object System.Data.sqlclient.sqlDataAdapter $command
$dataset = New-Object System.Data.DataSet
$adapter.Fill($dataSet) | Out-Null
$connection.Close()
$tableOutput = $dataSet.Tables
foreach($row in $tableOutput) {
$xml = $row | ConvertTo-Xml -NoTypeInformation -Depth 1
$xml.InnerXML
}
}
It works most of the time but, occasionally, exactly the same SELECT (except for the range) from the same database and table would throw the following exception:
Exception calling "Fill" with "1" argument(s): "Incorrect syntax near '>'."
At DBTest.ps1:22 char:18
+ $adapter.Fill <<<< ($dataSet) | Out-Null
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : DotNetMethodException
How to debug what rows and/or what data gets the Fill method to break?

Answer 1

As per comments, it was the SQL command itself. When you generate SQL commands make sure every variable goes through validation and sanity checks. As some comments suggested, logging queries can help with troubleshooting.