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1.Ê×ÏȵöÔmysql ÀïÃæµÄ²ÎÊý½øÐнéÉÜÏÂ:
procedure--in:ÊäÈë²ÎÊý,outÊä³ö²ÎÊý,inoutÕâ¸ö¾Í²»ÓÃ˵ÁË,´ó¸ÅÒ²²Âµ½ÁË
declare:ÉùÃ÷±äÁ¿.¼ÇÖ÷,ËùÓÐÉùÃ÷±ØÐëÔÚ·ÇÉùÃ÷Óï¾äÇ°Íê³É,·ñÔò»á±¨´í
2.mysql ³£Óú¯Êý½éÉÜ:
*.concat('s','a',5) ¿ÉÒÔÄÇÊýֵת»»³É×Ö·û´®,Ò²¿ÉÒÔ½øÐÐ×Ö·û´®µÄºÏ²¢
Èç:set str=concat('asd','ad',56) ----> str='asdad56'
declare num in;set num=156;set @ste=concat('',num)|(num);-->@str='156'
mysql> select CONCAT('My', NULL, 'QL');
¡¡¡¡ -> NULL
*.ASCII(str),·µ»Ø×Ö·û´®strµÄµÚÒ»¸ö×Ö·ûµÄASCIIÖµ(strÊÇ¿Õ´®Ê±·µ»Ø0)
Èç:mysql> select ASCII('2');-> 50
*.CONV(N,from_base,to_base),¶ÔÊý×ÖN½øÖÆת»»,²¢×ª»»Îª×Ö´®·µ»Ø(ÈκβÎÊýΪNULLʱ·µ»ØNULL,½øÖÆ·¶Î§Îª2-36ÖÆ, µ±to_baseÊǸºÊýʱN×÷ΪÓзûºÅÊý·ñÔò×÷ÎÞ·ûºÅÊý,CONVÒÔ64λµã¾«¶È¹¤×÷)
Èç:mysql> select CONV("a",16,2);
¡¡¡¡ -> '1010'
mysql> select CONV(-17,10,-18);
¡¡¡¡ -> '-H'
mysql> select CONV(10+"10"+'1
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