[SalesForce] SOQL query to return records with numeric values

Since you're dealing with a list of IDs, you want to use 'IN' instead of '='. The SOQL statement needs to end up looking like this

SELECT name FROM obj__c WHERE id IN ('a0OaxxxxxxxxMRDy2', 'a0OaxxxxxxxxMRDy2')

Edit by OP: it's been a while since I had the problem, but I've put this in my original post and as per Ratan's suggestion, I should mark this as accepted answer:

var records = {!GETRECORDIDS($ObjectType.obj__c)}.toString().replace(/,/g , "','"); 
var soqlQ="SELECT name FROM obj__c WHERE Id in ('"+records+"')"; 

You can't actually use a controler (directly) from a visualforce email template. Instead, you'll need to write a visualforce component, and include the component in your template. (You can write a controller for the component, but not for the email template.)

crop1645's question about having multiple contracts associated with an account is important to consider too.

Here's how I would approach this:

• Create a very basic email template containing a custom component. (Plan on putting most of the dynamic content in the component, not the template.)
• Make the relatedToType of your email template "Contract" (instead of "Account"). That way you'll know exactly which Contract you're dealing with.
• Pass the Contract ID into the component so you'll be able to reference it from the component's controller.
• In the controller, you can use the Contract ID to query for any info you need from the Contract and it's associated Account. Use that info to design your email inside the component.

Something like this:

Email template:

<messaging:emailTemplate relatedToType="Contract" subject="...">
  <messaging:htmlBody>
      Lorem Ipsum dolor bla bla bla...
      <c:EmailBodyContent theContractID="{!relatedTo.ID}">
  </messaging:htmlBody>
</messaging:emailTemplate>

Visualforce component: (EmailBodyContent.component)

<apex:component access="global" controller="myController">
  <apex:attribute name="theContractID" description="..." type="string" assignTo="{!conID}"/>
  <apex:outputText>
    Regarding the contract starting on {!theContract.StartDate} for {!theAccount.Name}...
  </apex:outputText>
</apex:component>

Component controller

Public class myController{
  public String conID {get; set;}
  public Account theAccount {get; set;}
  public Contract theContract {get; set;}

  theContract = [SELECT Id, StartDate, AccountID FROM Contract WHERE Id = :conID LIMIT 1];
  theAccount = [SELECT Id, Name FROM Account WHERE Id = :theContract.AccountID LIMIT 1];
}