How to get pool connection in multidbconnection

BIZ TMS XData
1
I tried to modify the multitenantbyheader demo by entering two databases that have different structures. I want to make a service, and the service will be accessed by the two databases. I try to do it like this:

function TGetAllService.getAllData(AGuid: string): TALLDATA;

var
  Manager1: TObjectManager;
  Manager2: TObjectManager;
begin
  TXDataOperationContext.Current.Request.Headers.SetValue('database-name',DB1);
  Manager1 := TXDataOperationContext.Current.CreateManager(TMappingExplorer.Get('Model1'));

  TXDataOperationContext.Current.Request.Headers.SetValue('database-name',DB2);
  Manager2 := TXDataOperationContext.Current.CreateManager(TMappingExplorer.Get('Mode2'));


but the manager will connect first in the first place. How do I access both databases in the same service?

and I add a model to each entity.
2
I tried this approach by starting a new project without taking a multitenant demo.

unit ConnectionModule

class function TFireDacFirebirdConnection.CreateCustomeConnection(FileName: string): IDBConnection;
var
  DataModule: TFireDacFirebirdConnection;
begin
  DataModule := TFireDacFirebirdConnection.Create(nil);
  DataModule.Connection.DriverName := 'FB';
  DataModule.Connection.Params.Database := FileName;
  DataModule.Connection.Params.UserName := 'SYSDBA';
  DataModule.Connection.Params.Password := 'masterkey';
  Result := TFireDacConnectionAdapter.Create(DataModule.Connection, 'Firebird', DataModule);
end;

unit ServiceImplementation

var
  ConnectionA, ConnectionB: IDBConnection;
  ManagerA, ManagerB: TObjectManager;
begin
  ConnectionA := TFireDacFirebirdConnection.CreateCustomeConnection(DBa);
  ManagerA := TObjectManager.Create(ConnectionA, TMappingExplorer.Get ('Ma'));
  TXDataOperationContext.Current.Handler.ManagedObjects.Add(ManagerA);

  ConnectionB := TFireDacFirebirdConnection.CreateCustomeConnection(DBb);
  ManagerB := TObjectManager.Create(ConnectionB, TMappingExplorer.Get ('Mb'));
  TXDataOperationContext.Current.Handler.ManagedObjects.Add(ManagerB);

my question, is it safe to use this method?
I've tried it, and data from DBa and DBb can be returned correctly by XData.
3

Yes, it's safe, and makes more sense since your databases have different structures.

You could also use a connection pool instead of creating one IDBConnection for each request. 
4
Thanks Wagner,

but how to choose the connection that I want from the connection pool, for example in my pool I have 3 databases that I add when the application starts.

const
  HETT_DB = 'C:\database\HETT_.FDB';
  KWLL_DB = 'C:\database\KWLL_.FDB';
  GTAA_DB = 'C:\database\GTAA_.FDB';
  .....

procedure TForm1.FormShow(Sender: TObject);
begin
  ServerByHeaderModule.AddDatabase(HETT_DB);
  ServerByHeaderModule.AddDatabase(KWLL_DB);
  ServerByHeaderModule.AddDatabase(GTAA_DB);
  btStartStop.Click;
end;



procedure TServerByHeaderModule.AddDatabase(DBName: string);
var
  Pool: IDBConnectionPool;
begin
  Pool := CreateConnectionPool(DBName);
  FMultiPool.AddOrSetPool(DBName, Pool);
end;

5

The ServerByHeaderModle would automatically choose the pool based on the client request header. Since you are using a different approach, you could simply save a reference to the created pool in some global variable and retrieve a connection from it, if you know from which database you need to get a connection to.