本文內(nèi)容來(lái)源于網(wǎng)絡(luò)，非原創(chuàng)，放到這里只是為了查閱方便。

在SQL Server中，可以用此函數(shù)：

CREATE function [dbo].[fn_GetPy](@str nvarchar(500)) 
returns nvarchar(500) 
--WITH ENCRYPTION 
as 
begin 
declare @intLen int 
declare @strRet nvarchar(500) 
declare @temp nvarchar(100) 
set @intLen = len(@str) 
set @strRet = '' 
while @intLen > 0 
begin 
set @temp = '' 
select @temp = case 
when substring(@str,@intLen,1) >= '帀' then 'Z' 
when substring(@str,@intLen,1) >= '丫' then 'Y' 
when substring(@str,@intLen,1) >= '夕' then 'X' 
when substring(@str,@intLen,1) >= '屲' then 'W' 
when substring(@str,@intLen,1) >= '他' then 'T' 
when substring(@str,@intLen,1) >= '仨' then 'S' 
when substring(@str,@intLen,1) >= '呥' then 'R' 
when substring(@str,@intLen,1) >= '七' then 'Q' 
when substring(@str,@intLen,1) >= '妑' then 'P' 
when substring(@str,@intLen,1) >= '噢' then 'O' 
when substring(@str,@intLen,1) >= '拏' then 'N' 
when substring(@str,@intLen,1) >= '嘸' then 'M' 
when substring(@str,@intLen,1) >= '垃' then 'L' 
when substring(@str,@intLen,1) >= '咔' then 'K' 
when substring(@str,@intLen,1) >= '丌' then 'J' 
when substring(@str,@intLen,1) >= '鉿' then 'H' 
when substring(@str,@intLen,1) >= '旮' then 'G' 
when substring(@str,@intLen,1) >= '發(fā)' then 'F' 
when substring(@str,@intLen,1) >= '妸' then 'E' 
when substring(@str,@intLen,1) >= '咑' then 'D' 
when substring(@str,@intLen,1) >= '嚓' then 'C' 
when substring(@str,@intLen,1) >= '八' then 'B' 
when substring(@str,@intLen,1) >= '吖' then 'A' 
else rtrim(ltrim(substring(@str,@intLen,1))) 
end 
--對(duì)于漢字特殊字符，不生成拼音碼 
if (ascii(@temp)>127) set @temp = '' 
--對(duì)于英文中小括號(hào)，不生成拼音碼 
if @temp = '(' or @temp = ')' set @temp = '' 
select @strRet = @temp + @strRet 
set @intLen = @intLen - 1 
end 
return lower(@strRet) 
end 

在Java中可以用此方法

import java.io.UnsupportedEncodingException;  
  
/** 
 * 取得給定漢字串的首字母串,即聲母串 
 * Title: ChineseCharToEn 
 * @date 2004-02-19 注：只支持GB2312字符集中的漢字 
 */  
public final class ChineseCharToEn {  
    private final static int[] li_SecPosValue = { 1601, 1637, 1833, 2078, 2274,  
            2302, 2433, 2594, 2787, 3106, 3212, 3472, 3635, 3722, 3730, 3858,  
            4027, 4086, 4390, 4558, 4684, 4925, 5249, 5590 };  
    private final static String[] lc_FirstLetter = { "a", "b", "c", "d", "e",  
            "f", "g", "h", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s",  
            "t", "w", "x", "y", "z" };  
  
    /** 
     * 取得給定漢字串的首字母串,即聲母串 
     * @param str 給定漢字串 
     * @return 聲母串 
     */  
    public String getAllFirstLetter(String str) {  
        if (str == null || str.trim().length() == 0) {  
            return "";  
        }  
  
        String _str = "";  
        for (int i = 0; i < str.length(); i++) {  
            _str = _str + this.getFirstLetter(str.substring(i, i + 1));  
        }  
  
        return _str;  
    }  
  
    /** 
     * 取得給定漢字的首字母,即聲母 
     * @param chinese 給定的漢字 
     * @return 給定漢字的聲母 
     */  
    public String getFirstLetter(String chinese) {  
        if (chinese == null || chinese.trim().length() == 0) {  
            return "";  
        }  
        chinese = this.conversionStr(chinese, "GB2312", "ISO8859-1");  
  
        if (chinese.length() > 1) // 判斷是不是漢字  
        {  
            int li_SectorCode = (int) chinese.charAt(0); // 漢字區(qū)碼  
            int li_PositionCode = (int) chinese.charAt(1); // 漢字位碼  
            li_SectorCode = li_SectorCode - 160;  
            li_PositionCode = li_PositionCode - 160;  
            int li_SecPosCode = li_SectorCode * 100 + li_PositionCode; // 漢字區(qū)位碼  
            if (li_SecPosCode > 1600 && li_SecPosCode < 5590) {  
                for (int i = 0; i < 23; i++) {  
                    if (li_SecPosCode >= li_SecPosValue[i]  
                            && li_SecPosCode < li_SecPosValue[i + 1]) {  
                        chinese = lc_FirstLetter[i];  
                        break;  
                    }  
                }  
            } else // 非漢字字符,如圖形符號(hào)或ASCII碼  
            {  
                chinese = this.conversionStr(chinese, "ISO8859-1", "GB2312");  
                chinese = chinese.substring(0, 1);  
            }  
        }  
  
        return chinese;  
    }  
  
    /** 
     * 字符串編碼轉(zhuǎn)換 
     * @param str 要轉(zhuǎn)換編碼的字符串 
     * @param charsetName 原來(lái)的編碼 
     * @param toCharsetName 轉(zhuǎn)換后的編碼 
     * @return 經(jīng)過(guò)編碼轉(zhuǎn)換后的字符串 
     */  
    private String conversionStr(String str, String charsetName,String toCharsetName) {  
        try {  
            str = new String(str.getBytes(charsetName), toCharsetName);  
        } catch (UnsupportedEncodingException ex) {  
            System.out.println("字符串編碼轉(zhuǎn)換異常：" + ex.getMessage());  
        }  
        return str;  
    }  
  
    public static void main(String[] args) {  
        ChineseCharToEn cte = new ChineseCharToEn();  
        System.out.println("獲取拼音首字母："+ cte.getAllFirstLetter("北京歡迎您"));  
    }  
  
}

參考鏈接：(https://blog.csdn.net/xys_777/article/details/5744371)
(https://blog.csdn.net/zhhandcsdn/article/details/78183260)