Einen gecasteten String mit Zeichen auffüllen in einer SQL Anweisung

[RWarnecke]

Wenn ich die TAdvDBLookupCombobox richtig verstanden habe, kann ich in der Auswahl nur Strings anzeigen lassen. Also muss ich doch ein Integer zu einem String casten.

Edit:
Hier mal die komplette SQL-Anweisung, vielleicht hilft es ja zum besseren Verständnis für mein Problem.

Code:

select facility.*, 
       province.AaLong as AaProvinceLong, 
       province.AaShort as AaProvinceShort,  
       province.AaCenter as AaProvinceCenter,
       district.AaName as AaDistrictName, 
       country.AaLong as AaCountryLong,
       country.AaShort as AaCountryShort,
       facility_type.AaShort as AaFacilityTypeShort,
       facility_type.AaLong as AaFacilityTypeLong,
       (AaProvinceShort + AaFacilityTypeShort + cast(facility.AiCode as String)) as AaCode
   from (facility
         LEFT JOIN province
         ON facility.AiProvince = province.SiProvince
         LEFT JOIN district
         ON facility.AiDistrict = district.SiDistrict
         LEFT JOIN country
         ON facility.AiCountry = country.SiCountry
         LEFT JOIN facility_type
         ON facility.AiFacilitytype = facility_type.SiFacilitytype
         )
   order by AaCode ASC;

Es geht dabei um den AiCode. Dieser soll immer vierstellig angezeigt werden.