multi-part identifier could not be bound error

Question

Here is my query:

IF OBJECT_ID('NPWAS1513.dbo.usp_MSPEX_QLK_Billing_Fact_Load') IS NOT NULL 
  DROP PROCEDURE dbo.usp_MSPEX_QLK_Billing_Fact_Load;
GO

CREATE PROCEDURE usp_MSPEX_QLK_Billing_Fact_Load
  @create_timestamp datetime,
  @update_timestamp datetime,
  @create_user varchar(50),
  @update_user varchar(50),
  @dbProdServ varchar(50)

AS

  print 'dbProdServ is:'+ @dbProdServ;
  print 'current_user is:' +@current_user;

  DECLARE @sSQL AS VARCHAR(MAX);

  SET @sSQL = ''
  SET @sSQL =  'set identity_insert ' + @dbProdServ + '.mspex_qlk_billing_fact ON'
  EXEC(@sSQL);

  SET @sSQL = 'INSERT INTO ' + @dbProdServ +'.mspex_qlk_billing_fact
    (project_id,
     billing_year,
     billing_month,
     billing_month_desc,
     billing_date_id,
     projected_bill_amount,
     billed_year_to_date_amount,
     billed_inception_to_date_amount,
     remaining_bill_amount,
     actual_billed_amount,
     current_billing_percent,
     previous_billing_percent,
     billing_pct_diff,
     billing_type,
     final_bill_ind,
     last_in_progress_date,
     current_record_ind,
     load_time_stamp,
     total_contract_period,
     contract_period_current_year,
     partial_bill,
     create_timestamp,
     create_user,
     update_timestamp,
     update_user)
     SELECT project_dim.project_id,
       billing_final_data.billingyear,
       billing_final_data.billingmonth,
       billing_final_data.billingmonthdesc,
       Time_Dim.Time_ID,
       billing_final_data.projected_bill_amount,
       billing_final_data.billed_year_todate_amount,
       billing_final_data.billed_inception_todate_amount,
       billing_final_data.remaining_bill_amount,
       billing_final_data.actual_billed_amount,
       billing_final_data.current_billing_percent,
       billing_final_data.previous_billing_percent,
       billing_final_data.billing_pct_diff,
       billing_final_data.billing_type,
       billing_final_data.final_bill_ind,
       billing_final_data.last_in_progress_date,
       billing_final_data.current_record_ind,
       billing_final_data.load_time_stamp,
       billing_final_data.[Total Contract Period],
       billing_final_data.[Contract Period Current Year],
       billing_final_data.[Partial Bill],'''+
       CAST(@create_timestamp as varchar(max)) + ''',''' +
       @create_user           + ''','''+
       CAST(@update_timestamp as varchar(50)) +''','''+
       @update_user           + '''
       FROM '+ 
       @dbProdServ +'.mspex_qlk_project_dim project_dim,'+
       @dbProdServ +'.mspex_rpt_billing_final_data billing_final_data,'+
       @dbProdServ + '.MSPEX_QLK_Time_Dim Time_Dim
WHERE
  project_dim.myproject_project_uid = billing_final_data.projectuid
  AND'''+ convert(datetime, cast(billing_final_data.[BillingMonth] as nvarchar(2)) + '''/01/''' + cast(billing_final_data.[billingyear] as nvarchar(4)), 101) +''' + = Time_Dim.Time_Date'; 

  BEGIN TRANSACTION
    EXEC(@sSQL)
  COMMIT TRANSACTION

I get the error msg:
Msg 4104, Level 16, State 1, Procedure usp_MSPEX_QLK_Billing_Fact_Load, Line 23
The multi-part identifier "mspex_rpt_billing_final_data.BillingMonth" could not be bound.
Msg 4104, Level 16, State 1, Procedure usp_MSPEX_QLK_Billing_Fact_Load, Line 23
The multi-part identifier "billing_final_data.billingyear" could not be bound.
Msg 207, Level 16, State 1, Procedure usp_MSPEX_QLK_Billing_Fact_Load, Line 83
Invalid column name 'BillingMonth'.
Msg 207, Level 16, State 1, Procedure usp_MSPEX_QLK_Billing_Fact_Load, Line 84
Invalid column name 'billingyear'.

I checked the column names, etc. and things are fine. In fact, I directly dragged the table name and column name to ensure that it is correct.

Answer 1

If you want a guess, based on the naming in the other table, I think you're missing some underscores:

...
SELECT project_dim.project_id,
       billing_final_data.billing_year,
       billing_final_data.billing_month,
...