我有以下 SQL CLR C# UDF：
这基本上接受两个参数，一个国家名称和一个邮政编码，然后返回以国家代码为前缀的邮政编码。非常基本的东西，但我对它的性能不满意。
我听说将这个国家和代码列表添加为资源然后填充列表可能会有所帮助，但我不知道该怎么做？
有任何想法吗？
using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
public partial class UserDefinedFunctions
{
[Microsoft.SqlServer.Server.SqlFunction]
public static SqlString clrFn_AddCountryCode(string theCountry, string thePostcode)
{
if (thePostcode.Length == 0 || String.IsNullOrEmpty(thePostcode)) { return (SqlString)(""); }
else if (theCountry == "FRENCH POLYNESIA") { return new SqlString("183" + thePostcode); }
else if (theCountry == "GUADELOUPE") { return new SqlString("181" + thePostcode); }
else if (theCountry == "ALAND") { return new SqlString("360" + thePostcode); }
else if (theCountry == "AFGHANISTAN") { return new SqlString("100" + thePostcode); }
else if (theCountry == "ALBANIA") { return new SqlString("101" + thePostcode); }
else if (theCountry == "ALGERIA") { return new SqlString("102" + thePostcode); }
else if (theCountry == "AMERICAN SAMOA") { return new SqlString("103" + thePostcode); }
else if (theCountry == "ANDORRA") { return new SqlString("104" + thePostcode); }
else if (theCountry == "ANGOLA") { return new SqlString("105" + thePostcode); }
else if (theCountry == "ANGUILLA") { return new SqlString("106" + thePostcode); }
else if (theCountry == "ANTIGUA & BARBUDA") { return new SqlString("107" + thePostcode); }
else if (theCountry == "ARGENTINA") { return new SqlString("108" + thePostcode); }
else if (theCountry == "ARMENIA") { return new SqlString("109" + thePostcode); }
else if (theCountry == "ARUBA") { return new SqlString("110" + thePostcode); }
else if (theCountry == "ASCENSION ISLAND") { return new SqlString("111" + thePostcode); }
else if (theCountry == "AUSTRALIA") { return new SqlString("112" + thePostcode); }
else if (theCountry == "AUSTRIA") { return new SqlString("113" + thePostcode); }
else if (theCountry == "AZERBAIJAN") { return new SqlString("114" + thePostcode); }
else if (theCountry == "BAHAMAS") { return new SqlString("115" + thePostcode); }
else if (theCountry == "BAHRAIN") { return new SqlString("116" + thePostcode); }
else if (theCountry == "BANGLADESH") { return new SqlString("117" + thePostcode); }
else if (theCountry == "BARBADOS") { return new SqlString("118" + thePostcode); }
else if (theCountry == "BELARUS") { return new SqlString("119" + thePostcode); }
else if (theCountry == "BELGIUM") { return new SqlString("120" + thePostcode); }
else if (theCountry == "BELIZE") { return new SqlString("121" + thePostcode); }
else if (theCountry == "BENIN") { return new SqlString("122" + thePostcode); }
else if (theCountry == "BERMUDA") { return new SqlString("123" + thePostcode); }
else if (theCountry == "BHUTAN") { return new SqlString("124" + thePostcode); }
else if (theCountry == "BOLIVIA") { return new SqlString("125" + thePostcode); }
else if (theCountry == "BOSNIA & HERZEGOVINA") { return new SqlString("128" + thePostcode); }
else if (theCountry == "BOTSWANA") { return new SqlString("129" + thePostcode); }
else if (theCountry == "BRAZIL") { return new SqlString("130" + thePostcode); }
else if (theCountry == "BRITISH INDIAN OCEAN TERRITORY") { return new SqlString("131" + thePostcode); }
else if (theCountry == "BRITISH VIRGIN ISLANDS") { return new SqlString("132" + thePostcode); }
else if (theCountry == "BRUNEI DARUSSALAM") { return new SqlString("134" + thePostcode); }
else if (theCountry == "BULGARIA") { return new SqlString("135" + thePostcode); }
else if (theCountry == "BURKINA FASO") { return new SqlString("136" + thePostcode); }
else if (theCountry == "BURUNDI") { return new SqlString("138" + thePostcode); }
else if (theCountry == "CAMBODIA") { return new SqlString("139" + thePostcode); }
else if (theCountry == "CAMEROON") { return new SqlString("140" + thePostcode); }
else if (theCountry == "CANADA") { return new SqlString("141" + thePostcode); }
else if (theCountry == "CAPE VERDE") { return new SqlString("142" + thePostcode); }
else if (theCountry == "CAYMAN ISLANDS") { return new SqlString("144" + thePostcode); }
else if (theCountry == "CENTRAL AFRICAN REPUBLIC") { return new SqlString("145" + thePostcode); }
else if (theCountry == "CHAD") { return new SqlString("146" + thePostcode); }
else if (theCountry == "CHILE") { return new SqlString("147" + thePostcode); }
else if (theCountry == "CHINA") { return new SqlString("148" + thePostcode); }
else if (theCountry == "COLOMBIA") { return new SqlString("151" + thePostcode); }
else if (theCountry == "COMOROS") { return new SqlString("152" + thePostcode); }
else if (theCountry == "COOK ISLANDS") { return new SqlString("154" + thePostcode); }
else if (theCountry == "COSTA RICA") { return new SqlString("155" + thePostcode); }
else if (theCountry == "CÔTE D'IVOIRE") { return new SqlString("213" + thePostcode); }
else if (theCountry == "CROATIA") { return new SqlString("157" + thePostcode); }
else if (theCountry == "CUBA") { return new SqlString("158" + thePostcode); }
else if (theCountry == "CYPRUS") { return new SqlString("160" + thePostcode); }
else if (theCountry == "CZECH REPUBLIC") { return new SqlString("161" + thePostcode); }
else if (theCountry == "DEMOCRATIC REPUBLIC OF CONGO") { return new SqlString("351" + thePostcode); }
else if (theCountry == "DENMARK") { return new SqlString("162" + thePostcode); }
else if (theCountry == "DJIBOUTI") { return new SqlString("163" + thePostcode); }
else if (theCountry == "DOMINICA") { return new SqlString("164" + thePostcode); }
else if (theCountry == "DOMINICAN REPUBLIC") { return new SqlString("165" + thePostcode); }
else if (theCountry == "ECUADOR") { return new SqlString("168" + thePostcode); }
else if (theCountry == "EGYPT") { return new SqlString("169" + thePostcode); }
else if (theCountry == "EL SALVADOR") { return new SqlString("171" + thePostcode); }
else if (theCountry == "EQUATORIAL GUINEA") { return new SqlString("172" + thePostcode); }
else if (theCountry == "ERITREA") { return new SqlString("173" + thePostcode); }
else if (theCountry == "ESTONIA") { return new SqlString("174" + thePostcode); }
else if (theCountry == "ETHIOPIA") { return new SqlString("175" + thePostcode); }
else if (theCountry == "FALKLAND ISLANDS") { return new SqlString("177" + thePostcode); }
else if (theCountry == "FAROE ISLANDS") { return new SqlString("176" + thePostcode); }
else if (theCountry == "FIJI") { return new SqlString("178" + thePostcode); }
else if (theCountry == "FINLAND") { return new SqlString("179" + thePostcode); }
else if (theCountry == "FRANCE") { return new SqlString("180" + thePostcode); }
else if (theCountry == "FRENCH GUIANA") { return new SqlString("182" + thePostcode); }
else if (theCountry == "GABON") { return new SqlString("186" + thePostcode); }
else if (theCountry == "GAMBIA") { return new SqlString("187" + thePostcode); }
else if (theCountry == "GEORGIA") { return new SqlString("283" + thePostcode); }
else if (theCountry == "GERMANY") { return new SqlString("189" + thePostcode); }
else if (theCountry == "GHANA") { return new SqlString("190" + thePostcode); }
else if (theCountry == "GIBRALTAR") { return new SqlString("191" + thePostcode); }
else if (theCountry == "GREECE") { return new SqlString("192" + thePostcode); }
else if (theCountry == "GREENLAND") { return new SqlString("193" + thePostcode); }
else if (theCountry == "GRENADA") { return new SqlString("194" + thePostcode); }
else if (theCountry == "GUADELOUPE") { return new SqlString("195" + thePostcode); }
else if (theCountry == "GUAM") { return new SqlString("196" + thePostcode); }
else if (theCountry == "GUATEMALA") { return new SqlString("197" + thePostcode); }
else if (theCountry == "GUINEA") { return new SqlString("198" + thePostcode); }
else if (theCountry == "GUINEA BISSAU") { return new SqlString("199" + thePostcode); }
else if (theCountry == "GUYANA") { return new SqlString("200" + thePostcode); }
else if (theCountry == "HAITI") { return new SqlString("201" + thePostcode); }
else if (theCountry == "HONDURAS") { return new SqlString("203" + thePostcode); }
else if (theCountry == "HONG KONG") { return new SqlString("204" + thePostcode); }
else if (theCountry == "HUNGARY") { return new SqlString("205" + thePostcode); }
else if (theCountry == "ICELAND") { return new SqlString("206" + thePostcode); }
else if (theCountry == "INDIA") { return new SqlString("207" + thePostcode); }
else if (theCountry == "INDONESIA") { return new SqlString("208" + thePostcode); }
else if (theCountry == "IRAN") { return new SqlString("209" + thePostcode); }
else if (theCountry == "IRAQ") { return new SqlString("210" + thePostcode); }
else if (theCountry == "IRELAND") { return new SqlString("170" + thePostcode); }
else if (theCountry == "ISRAEL") { return new SqlString("211" + thePostcode); }
else if (theCountry == "ITALY") { return new SqlString("212" + thePostcode); }
else if (theCountry == "JAMAICA") { return new SqlString("214" + thePostcode); }
else if (theCountry == "JAPAN") { return new SqlString("215" + thePostcode); }
else if (theCountry == "JORDAN") { return new SqlString("216" + thePostcode); }
else if (theCountry == "KAZAKHSTAN") { return new SqlString("217" + thePostcode); }
else if (theCountry == "KENYA") { return new SqlString("218" + thePostcode); }
else if (theCountry == "KIRIBATI") { return new SqlString("219" + thePostcode); }
else if (theCountry == "KOSOVO (UNMIK)") { return new SqlString("358" + thePostcode); }
else if (theCountry == "KUWAIT") { return new SqlString("220" + thePostcode); }
else if (theCountry == "KYRGYZSTAN") { return new SqlString("221" + thePostcode); }
else if (theCountry == "LAOS") { return new SqlString("222" + thePostcode); }
else if (theCountry == "LATVIA") { return new SqlString("223" + thePostcode); }
else if (theCountry == "LEBANON") { return new SqlString("224" + thePostcode); }
else if (theCountry == "LESOTHO") { return new SqlString("225" + thePostcode); }
else if (theCountry == "LIBERIA") { return new SqlString("226" + thePostcode); }
else if (theCountry == "LIBYA") { return new SqlString("227" + thePostcode); }
else if (theCountry == "LIECHTENSTEIN") { return new SqlString("228" + thePostcode); }
else if (theCountry == "LITHUANIA") { return new SqlString("229" + thePostcode); }
else if (theCountry == "LUXEMBOURG") { return new SqlString("230" + thePostcode); }
else if (theCountry == "MACAU") { return new SqlString("231" + thePostcode); }
else if (theCountry == "MACEDONIA") { return new SqlString("232" + thePostcode); }
else if (theCountry == "MADAGASCAR") { return new SqlString("233" + thePostcode); }
else if (theCountry == "MALAWI") { return new SqlString("234" + thePostcode); }
else if (theCountry == "MALAYSIA") { return new SqlString("235" + thePostcode); }
else if (theCountry == "MALDIVES") { return new SqlString("236" + thePostcode); }
else if (theCountry == "MALI") { return new SqlString("237" + thePostcode); }
else if (theCountry == "MALTA") { return new SqlString("238" + thePostcode); }
else if (theCountry == "MARSHALL ISLANDS") { return new SqlString("240" + thePostcode); }
else if (theCountry == "MARTINIQUE") { return new SqlString("241" + thePostcode); }
else if (theCountry == "MAURITANIA") { return new SqlString("242" + thePostcode); }
else if (theCountry == "MAURITIUS") { return new SqlString("243" + thePostcode); }
else if (theCountry == "MAYOTTE") { return new SqlString("244" + thePostcode); }
else if (theCountry == "MEXICO") { return new SqlString("245" + thePostcode); }
else if (theCountry == "MICRONESIA") { return new SqlString("246" + thePostcode); }
else if (theCountry == "MOLDOVA") { return new SqlString("247" + thePostcode); }
else if (theCountry == "MONACO") { return new SqlString("248" + thePostcode); }
else if (theCountry == "MONGOLIA") { return new SqlString("249" + thePostcode); }
else if (theCountry == "MONTENEGRO") { return new SqlString("357" + thePostcode); }
else if (theCountry == "MONTSERRAT") { return new SqlString("251" + thePostcode); }
else if (theCountry == "MOROCCO") { return new SqlString("252" + thePostcode); }
else if (theCountry == "MOZAMBIQUE") { return new SqlString("253" + thePostcode); }
else if (theCountry == "MYANMAR") { return new SqlString("254" + thePostcode); }
else if (theCountry == "NAMIBIA") { return new SqlString("255" + thePostcode); }
else if (theCountry == "NAURU") { return new SqlString("256" + thePostcode); }
else if (theCountry == "NEPAL") { return new SqlString("257" + thePostcode); }
else if (theCountry == "NETHERLANDS") { return new SqlString("259" + thePostcode); }
else if (theCountry == "NETHERLANDS ANTILLES") { return new SqlString("258" + thePostcode); }
else if (theCountry == "NEW CALEDONIA") { return new SqlString("260" + thePostcode); }
else if (theCountry == "NEW ZEALAND") { return new SqlString("261" + thePostcode); }
else if (theCountry == "NICARAGUA") { return new SqlString("262" + thePostcode); }
else if (theCountry == "NIGER") { return new SqlString("263" + thePostcode); }
else if (theCountry == "NIGERIA") { return new SqlString("264" + thePostcode); }
else if (theCountry == "NIUE") { return new SqlString("265" + thePostcode); }
else if (theCountry == "NORFOLK ISLAND") { return new SqlString("356" + thePostcode); }
else if (theCountry == "NORTH KOREA") { return new SqlString("266" + thePostcode); }
else if (theCountry == "NORTHERN MARIANA ISLANDS") { return new SqlString("267" + thePostcode); }
else if (theCountry == "NORWAY") { return new SqlString("268" + thePostcode); }
else if (theCountry == "OMAN") { return new SqlString("269" + thePostcode); }
else if (theCountry == "PAKISTAN") { return new SqlString("270" + thePostcode); }
else if (theCountry == "PALAU") { return new SqlString("271" + thePostcode); }
else if (theCountry == "PALESTINE") { return new SqlString("272" + thePostcode); }
else if (theCountry == "PANAMA") { return new SqlString("273" + thePostcode); }
else if (theCountry == "PAPUA NEW GUINEA") { return new SqlString("274" + thePostcode); }
else if (theCountry == "PARAGUAY") { return new SqlString("275" + thePostcode); }
else if (theCountry == "PERU") { return new SqlString("276" + thePostcode); }
else if (theCountry == "PHILIPPINES") { return new SqlString("277" + thePostcode); }
else if (theCountry == "PITCAIRN ISLAND") { return new SqlString("278" + thePostcode); }
else if (theCountry == "POLAND") { return new SqlString("279" + thePostcode); }
else if (theCountry == "PORTUGAL") { return new SqlString("280" + thePostcode); }
else if (theCountry == "PUERTO RICO") { return new SqlString("281" + thePostcode); }
else if (theCountry == "QATAR") { return new SqlString("282" + thePostcode); }
else if (theCountry == "REPUBLIC OF CONGO") { return new SqlString("361" + thePostcode); }
else if (theCountry == "REPUBLIC OF GEORGIA") { return new SqlString("188" + thePostcode); }
else if (theCountry == "REUNION") { return new SqlString("286" + thePostcode); }
else if (theCountry == "ROMANIA") { return new SqlString("287" + thePostcode); }
else if (theCountry == "RUSSIA") { return new SqlString("288" + thePostcode); }
else if (theCountry == "RWANDA") { return new SqlString("289" + thePostcode); }
else if (theCountry == "SAMOA") { return new SqlString("290" + thePostcode); }
else if (theCountry == "SAN MARINO") { return new SqlString("291" + thePostcode); }
else if (theCountry == "SANDWICH ISLANDS") { return new SqlString("362" + thePostcode); }
else if (theCountry == "SAO TOME & PRINCIPE") { return new SqlString("292" + thePostcode); }
else if (theCountry == "SAUDI ARABIA") { return new SqlString("293" + thePostcode); }
else if (theCountry == "SENEGAL") { return new SqlString("294" + thePostcode); }
else if (theCountry == "SERBIA") { return new SqlString("295" + thePostcode); }
else if (theCountry == "SEYCHELLES") { return new SqlString("296" + thePostcode); }
else if (theCountry == "SIERRA LEONE") { return new SqlString("298" + thePostcode); }
else if (theCountry == "SINGAPORE") { return new SqlString("284" + thePostcode); }
else if (theCountry == "SLOVAKIA") { return new SqlString("299" + thePostcode); }
else if (theCountry == "SLOVENIA") { return new SqlString("300" + thePostcode); }
else if (theCountry == "SOLOMON ISLANDS") { return new SqlString("302" + thePostcode); }
else if (theCountry == "SOMALIA") { return new SqlString("303" + thePostcode); }
else if (theCountry == "SOUTH AFRICA") { return new SqlString("304" + thePostcode); }
else if (theCountry == "SOUTH KOREA") { return new SqlString("359" + thePostcode); }
else if (theCountry == "SPAIN") { return new SqlString("305" + thePostcode); }
else if (theCountry == "SRI LANKA") { return new SqlString("306" + thePostcode); }
else if (theCountry == "ST HELENA") { return new SqlString("307" + thePostcode); }
else if (theCountry == "ST KITTS & NEVIS") { return new SqlString("308" + thePostcode); }
else if (theCountry == "ST LUCIA") { return new SqlString("309" + thePostcode); }
else if (theCountry == "ST PIERRE & MIQUELON") { return new SqlString("311" + thePostcode); }
else if (theCountry == "ST VINCENT & THE GRENADINES") { return new SqlString("312" + thePostcode); }
else if (theCountry == "SUDAN") { return new SqlString("313" + thePostcode); }
else if (theCountry == "SURINAME") { return new SqlString("314" + thePostcode); }
else if (theCountry == "SWAZILAND") { return new SqlString("315" + thePostcode); }
else if (theCountry == "SWEDEN") { return new SqlString("316" + thePostcode); }
else if (theCountry == "SWITZERLAND") { return new SqlString("317" + thePostcode); }
else if (theCountry == "SYRIA") { return new SqlString("318" + thePostcode); }
else if (theCountry == "TAIWAN") { return new SqlString("320" + thePostcode); }
else if (theCountry == "TAJIKISTAN") { return new SqlString("321" + thePostcode); }
else if (theCountry == "TANZANIA") { return new SqlString("322" + thePostcode); }
else if (theCountry == "THAILAND") { return new SqlString("324" + thePostcode); }
else if (theCountry == "TIMOR-LESTE") { return new SqlString("167" + thePostcode); }
else if (theCountry == "TOGO") { return new SqlString("325" + thePostcode); }
else if (theCountry == "TOKELAU") { return new SqlString("326" + thePostcode); }
else if (theCountry == "TONGA") { return new SqlString("327" + thePostcode); }
else if (theCountry == "TRINIDAD & TOBAGO") { return new SqlString("328" + thePostcode); }
else if (theCountry == "TRISTAN DA CUNHA") { return new SqlString("355" + thePostcode); }
else if (theCountry == "TUNISIA") { return new SqlString("330" + thePostcode); }
else if (theCountry == "TURKEY") { return new SqlString("331" + thePostcode); }
else if (theCountry == "TURKMENISTAN") { return new SqlString("332" + thePostcode); }
else if (theCountry == "TURKS AND CAICOS") { return new SqlString("333" + thePostcode); }
else if (theCountry == "TUVALU") { return new SqlString("334" + thePostcode); }
else if (theCountry == "UGANDA") { return new SqlString("335" + thePostcode); }
else if (theCountry == "UKRAINE") { return new SqlString("336" + thePostcode); }
else if (theCountry == "UNITED ARAB EMIRATES") { return new SqlString("337" + thePostcode); }
else if (theCountry == "UNITED KINGDOM") { return new SqlString("338" + thePostcode); }
else if (theCountry == "URUGUAY") { return new SqlString("340" + thePostcode); }
else if (theCountry == "UZBEKISTAN") { return new SqlString("342" + thePostcode); }
else if (theCountry == "VANUATU") { return new SqlString("343" + thePostcode); }
else if (theCountry == "VATICAN CITY") { return new SqlString("344" + thePostcode); }
else if (theCountry == "VENEZUELA") { return new SqlString("345" + thePostcode); }
else if (theCountry == "VIETNAM") { return new SqlString("346" + thePostcode); }
else if (theCountry == "UNITED STATES") { return new SqlString("339" + thePostcode); }
else if (theCountry == "US VIRGIN ISLANDS") { return new SqlString("341" + thePostcode); }
else if (theCountry == "WALLIS & FUTUNA") { return new SqlString("347" + thePostcode); }
else if (theCountry == "YEMEN") { return new SqlString("349" + thePostcode); }
else if (theCountry == "ZAMBIA") { return new SqlString("352" + thePostcode); }
else if (theCountry == "ZIMBABWE") { return new SqlString("353" + thePostcode); }
else return new SqlString ("");
}
}