CRM 2013: fn_GetLocalizedLabel in custom CRM SQL Report and LabelTypeCode parameter

Today I tried to migrate a custom CRM 4.0 SQL report to the a CRM 2013 SQL report.
In the report designer I hit the preview button and received the following error:

TITLE: Microsoft SQL Server Report Designer
------------------------------
An error occurred while executing the query.
An insufficient number of arguments were supplied for the procedure or function dbo.fn_GetLocalizedLabel.

OK, this means the SQL function "fn_GetLocalizedLabel" in CRM 4.0 used to have one parameter less than in CRM 2011 or CRM 2013.

After comparing the paramter signatures with the SQL database version I found this definition:

function [dbo].[fn_GetLocalizedLabel] (
    @ObjectId uniqueidentifier,
    @ColumnName nvarchar(255),
    @LabelTypeCode int,
    @LanguageCode int
)
returns nvarchar(255)
as
begin
    declare @LocalizedLabel     nvarchar(255)
   
    begin
        select @LocalizedLabel = l.Label
            from LocalizedLabelView l
            where @ObjectId = l.ObjectId
            and @LanguageCode = l.LanguageId
            and @ColumnName = l.ObjectColumnName
            and @LabelTypeCode = l.LabelTypeCode
    end
    return @LocalizedLabel
end

The missing parameter was the "LabelTypeCode".

So I thought what in the world do I have to put in here??
I search in Google and even the CRM SDK documentation does not tell us what this parameter means.

Finally, my last resort is usually to check the CRM assemblies with a Reflector or JustDecompile tool to find out how to deal with this.

Immediately I found this:

namespace Microsoft.Crm.Metadata
{
    public enum LabelTypeCode
    {
        [EnumIntroducedVersion("5.0.0.0", true)]
        Entity,
        [EnumIntroducedVersion("5.0.0.0", true)]
        Attribute,
        [EnumIntroducedVersion("5.0.0.0", true)]
        AttributePicklistValue,
        [EnumIntroducedVersion("5.0.0.0", true)]
        EntityRelationshipRole,
        [EnumIntroducedVersion("5.0.0.0", true)]
        SavedQuery,
        [EnumIntroducedVersion("5.0.0.0", true)]
        Form,
        [EnumIntroducedVersion("5.0.0.0", true)]
        FormTab,
        [EnumIntroducedVersion("5.0.0.0", true)]
        FormSection,
        [EnumIntroducedVersion("5.0.0.0", true)]
        FormCell,
        [EnumIntroducedVersion("5.0.0.0", true)]
        SavedQueryVisualization,
        [EnumIntroducedVersion("5.0.0.0", true)]
        OptionSet,
        [EnumIntroducedVersion("5.0.0.0", true)]
        Solution,
        [EnumIntroducedVersion("5.0.0.0", true)]
        Publisher,
        [EnumIntroducedVersion("5.0.0.0", true)]
        Ribbon,
        [EnumIntroducedVersion("5.0.0.0", true)]
        TimeZoneDefinition,
        [EnumIntroducedVersion("5.0.0.0", true)]
        TimeZoneLocalizedName,
        [EnumIntroducedVersion("5.0.0.0", true)]
        WebResource,
        [EnumIntroducedVersion("5.0.0.0", true)]
        ManagedProperty,
        [EnumIntroducedVersion("5.0.0.0", true)]
        ComplexControl,
        [EnumIntroducedVersion("6.0.0.0", true)]
        Workflow
    }
}

Checking the LocalizedLabelView in the database I only found this information regarding the Labels (truncated data and columns for readability):

LocalizedLabelId	LocalizedLabelRowId	LanguageId	ObjectId	ObjectColumnName	Label	LabelTypeCode	ComponentState	IsManaged
E9158B76-…	7EDC933C-…	2052	C341B506-…	DisplayName	其他	2	0	1
F4F48DB1-…	5B90A8A8-…	2052	CDA38168-…	Description	地址 1 的送货方式。	10	0	1
C97111AD-…	063C23C1-…	1033	8734A095-…	Description	Position of the Sdk message response field	1	0	1

As you can see the LabelTypeCode contains integer values. But without the enum displayed above the table information would be meaningless as we do not know the purpose of the integer values.

Short reminder:
Enum values start to count from 0.
Meaning that Entity has the number 0, Attribute is 1 ...

This maps to this table:

LabelTypeCode	Integer
Entity	0
Attribute	1
AttributePicklistValue	2
EntityRelationshipRole	3
SavedQuery	4
Form	5
FormTab	6
FormSection	7
FormCell	8
SavedQueryVisualization	9
OptionSet	10
Solution	11
Publisher	12
Ribbon	13
TimeZoneDefinition	14
TimeZoneLocalizedName	15
WebResource	16
ManagedProperty	17
ComplexControl	18
Workflow	19

I hope this helps you to get a better understanding as well in any case you ever need to work with the LabelTypeCodes.