Run a SQL Script Against MySQL using Powershell

Question

I have a Powershell script that backs up my MySQL DB's each night using mysqldump. This all works fine but I would like to extend the script to update a reporting db (db1) from the backup of the prod db (db2). I have written the following test script but it does not work. I have a feeling the problem is the reading of the sql file to the CommandText but I am not sure how to debug.

[system.reflection.assembly]::LoadWithPartialName("MySql.Data")    
$mysql_server = "localhost"
$mysql_user = "root"
$mysql_password = "password"
write-host "Create coonection to db1"
# Connect to MySQL database 'db1'

$cn = New-Object -TypeName MySql.Data.MySqlClient.MySqlConnection
$cn.ConnectionString = "SERVER=$mysql_server;DATABASE=db1;UID=$mysql_user;PWD=$mysql_password"
$cn.Open()
write-host "Running backup script against db1"
# Run Update Script MySQL 
$cm = New-Object -TypeName MySql.Data.MySqlClient.MySqlCommand
$sql = Get-Content C:\db2.sql
$cm.Connection = $cn
$cm.CommandText = $sql
$cm.ExecuteReader()
write-host "Closing Connection"
$cn.Close()

Any assistance would be appreciated. Thanks.

Solution

This line:

$sql = Get-Content C:\db2.sql 

Returns an array of strings. When that gets assigned to something expecting a string then PowerShell will concatenate the array of strings into a single string using the contents of the $OFS (output field separator) variable. If this variable isn't set, the default separator is a single space. Try this instead and see if it works:

$sql = Get-Content C:\db2.sql 
...
$OFS = "`r`n"
$cm.CommandText = "$sql"

Or if you're on PowerShell 2.0:

$sql = (Get-Content C:\db2.sql) -join "`r`n"

Comments

[abarr]

Thanks Keith. I tried the above (I am using PS 1) but get an exception :

[abarr]

Exception calling "ExecuteReader" with "0" argument(s): "Fatal error encountered during command execution." At C:\mysqlbackup\scripts\mysqlbackup.ps1:86 char:18 + $cm.ExecuteReader <<<< () + CategoryInfo : NotSpecified: (:) [], MethodInvocationException + FullyQualifiedErrorId : DotNetMethodException

[abarr]

Keith, Sorry for the delay, was travelling for work and didn't get a chance to follow up. I have added it above. I added $OFS = "rn" after the Get-Content command. Thanks in advance.

[Keith Hill]

Looks like there's a SQL script error at line 86, column 18 of mysqlbackup.ps1. Anything odd going on at that location in your script?

[abarr]

Keith, it is the Execute call for the SQL Command. It only happens when I use $OFS. I have checked the script and the changes I made are in the .sql file and when I run it I pipe it to screen and I can see the sql but for some reason it does not reflect the changes (I added a table to the original DB).

[Keith Hill]

Try this $sql = [io.file]::ReadAllText('c:\db2.sql') to retrieve the script contents instead of Get-Content. At this point, $sql will contain the exact script contents as a single string.