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mysql> select ASCII('2');
-> 50
mysql> select ASCII(2);
-> 50
mysql> select ASCII('dx');
-> 100
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mysql> select ORD('2');
-> 50
CONV(N,from_base,to_base) ÔÚ²»Í¬µÄÊý×Ö»ùÖ®¼ä±ä»»Êý×Ö¡£·µ»ØÊý×ÖNµÄ×Ö·û´®Êý×Ö£¬´Ófrom_base»ù±ä»»Îªto_base»ù£¬Èç¹ûÈκβÎÊýÊÇNULL£¬·µ»ØNULL¡£²ÎÊýN½âÊÍΪһ¸öÕûÊý£¬µ«ÊÇ¿ÉÒÔÖ¸¶¨ÎªÒ»¸öÕûÊý»òÒ»¸ö×Ö·û´®¡£×îС»ùÊÇ2ÇÒ×î´óµÄ»ùÊÇ36¡£Èç¹ûto_baseÊÇÒ»¸ö¸ºÊý£¬N±»ÈÏΪÊÇÒ»¸öÓзûºÅÊý£¬·ñÔò£¬N±»µ±×÷ÎÞ·ûºÅÊý¡£ CONVÒÔ64λµã¾«¶È¹¤×÷¡£
mysql> select CONV("a",16,2);
-> '1010'
mysql> select CONV("6E",18,8);
-> '172'
mysql> select CONV(-17,10,-18);
-> '-H'
mysql> select CONV(10+"10"+'10'+0xa,10,10);
-> '40'
BIN(N) ·µ»Ø¶þ½øÖÆÖµNµÄÒ»¸ö×Ö·û´®±íʾ£¬ÔÚ´ËNÊÇÒ»¸ö³¤ÕûÊý(BIGINT)Êý×Ö£¬ÕâµÈ¼ÛÓÚCONV(N,10,2)¡£Èç¹ûNÊÇNULL£¬·µ»ØNULL¡£
mysql> select BIN(12);
-> '1100'
OCT(N) ·µ»Ø°Ë½øÖÆÖµNµÄÒ»¸ö×Ö·û´®µÄ±íʾ£¬ÔÚ´ËNÊÇÒ»¸ö³¤ÕûÐÍÊý×Ö£¬ÕâµÈ¼ÛÓÚCONV(N,10,8)¡£Èç¹ûNÊÇNULL£¬·µ»ØNULL¡£
mysql> select OCT(12);
-> '14'
HEX(N) ·µ»ØÊ®Áù½øÖÆÖµNÒ»¸ö×Ö·û´®µÄ±íʾ£¬ÔÚ´ËNÊÇÒ»¸ö³¤ÕûÐÍ(BIGINT)Êý×Ö£¬ÕâµÈ¼ÛÓÚCONV(N,10,16)¡£Èç¹ûNÊÇNULL£¬·µ»ØNULL¡£
mysql> select HEX(255);
-> 'FF'
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mysql> select CHAR(77,121,83,81,'76');
-> 'MySQL'
mysql> select CHAR(77,77.3,'77.3');
-> 'MMM'
CONCAT(str1,str2,...) ·µ»ØÀ´×ÔÓÚ²ÎÊýÁ¬½áµÄ×Ö·û´®¡£Èç¹ûÈκβÎÊýÊÇNULL£¬·µ»ØNULL¡£¿ÉÒÔÓг¬¹ý
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LOCK TABLES tbl_name [AS alias] {READ [LOCAL] | [LOW_PRIORITY] WRITE}
[, tbl_name [AS alias] {READ [LOCAL] | [LOW_PRIORITY] WRITE} ...]
...
UNLOCK TABLES
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cd /opt
wget http://mysql-cacti-templates.googlecode.com/files/mysql-cacti-templates-1.1.6.tar.gz
tar -xzvf mysql-cacti-templates-1.1.2.tar.gz
cp /opt/mysql-cacti-templates-1.1.2 ......
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| f_PY | cBegin | cEnd |
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| A | 45217 | 45252 | & ......