SQL Server - How to capture database errors

One very useful addition to a database I have found recently is to capture database errors in a try...catch block and storing the information in a table. Here is what I did:

Table to store the error information:

CREATE TABLE dbo.DBErrors (
  DBErrorID INT IDENTITY
 ,Raised DATETIME NULL CONSTRAINT DF_DBErrors_Raised DEFAULT (GETDATE())
 ,Number INT NULL
 ,Severity INT NULL
 ,StateNumber INT NULL
 ,StoredProcedure NVARCHAR(128) NULL
 ,Line INT NULL
 ,ErrorMessage NVARCHAR(4000) NULL
 ,CONSTRAINT PK_DBErrors PRIMARY KEY CLUSTERED (DBErrorID)
) ON [PRIMARY]

Then I wrote a stored procedure to write to the table:

CREATE PROCEDURE dbo.DBErrorInsert
AS
BEGIN
DECLARE @DBErrorsExist bit;
  SET NOCOUNT ON;
  
  SELECT TOP (1) @DBErrorsExist = TableExists FROM dbo.efn_TableExists('DBErrors');
IF (@DBErrorsExist = 1)
BEGIN
INSERT INTO DBErrors (Number, Severity, StateNumber, StoredProcedure, Line,   ErrorMessage) VALUES ( 
ERROR_NUMBER(),  
ERROR_SEVERITY(),  
ERROR_STATE(),  
ERROR_PROCEDURE(),  
ERROR_LINE(),  
ERROR_MESSAGE());
    RETURN -2;
END
  ELSE
  BEGIN
    RETURN -1;
  END;
END;

Then where I wanted to capture any errors i.e. in a stored procedure I did the following:

BEGIN TRY
  ... Stored proc code
END TRY
BEGIN CATCH
  EXEC dbo.DBErrorInsert;
END CATCH

When an error occurs in the try...catch block it writes the error information including the line the error was triggered to a record in the table.

SQL Server - List all fixed length fields in a database

I noticed that a field in a database had been set to a nchar(), this means it's a fixed length and in a result query had trailing spaces. The 2 options I had were to change the field type to nvarchar() or add a RTRIM() to the field and alias it. To identify any other fields that were like this I ran the following query:

SELECT 
    TABLE_SCHEMA,
    TABLE_NAME, 
    COLUMN_NAME, 
    DATA_TYPE, 
    CHARACTER_MAXIMUM_LENGTH AS Defined_Length
FROM INFORMATION_SCHEMA.COLUMNS
WHERE DATA_TYPE IN ('char', 'nchar')
ORDER BY TABLE_NAME;

Mouse Wheel and TScrollBox

We had an issue where there was a TScrollbox on a form and the mouse wheel would not do the vertical scroll. The simplest solution I found for this was to do the following in the forms 'OnMouseWheel' event.

if MyScrollBox.BoundsRect.Contains(MyScrollBox.Parent.ScreenToClient(MousePos)) then
begin
  MyScrollBox.VertScrollBar.Position := MyScrollBox.VertScrollBar.Position -                   WheelDelta;
  Handled := True;
end;