如何通過SQL語句為某個已有字段添加自增屬性？mysqlalter tablettchangeidid intdefaultnull;Query就ok啦,1rowaffected(0.23sec)Re

如何通過SQL語句為某個已有字段添加自增屬性？

mysqlalter tablettchangeidid intdefaultnull;

Query就ok啦,1rowaffected(0.23sec)

Records:1Duplicates:0Warnings:0

mysqlshowtablestt;

-----------------------------------------------------------------------------------------------------------------------------------------------------------------

|Table|tables

|

-----------------------------------------------------------------------------------------------------------------------------------------------------------------

|tt|table`tt`(

`id`int(11)NOTbooleanDEFAULT0,

`Field1`varchar(255)DEFAULTNULL,

PRIMARY KEY(`id`)

)ENGINEInnoDBDEFAULTCHARSETutf8|

-----------------------------------------------------------------------------------------------------------------------------------------------------------------

1rowinset(0.02sec)

mysqlalter tablettmodifyid intnotnullauto_increment;

Query就ok啦,1rowaffected(0.20sec)

Records:1Duplicates:0Warnings:0

mysqlselect*acrosstt;

------------

|id|Field1|

------------

|1|人|

------------

在PL/SQL Developer中如何設(shè)置SQL窗口里的字符編碼格式？

在windows中修改一個名為“NLS_LANG”的系統(tǒng)環(huán)境變量，系統(tǒng)設(shè)置其值為“SIMPLIFIEDCHINESE_CHINA.ZHS16GBK”，然后把再重啟pl/sqldeveloper，那樣檢索出去的中文內(nèi)容就應(yīng)該不會是了。要是想可以轉(zhuǎn)換為UTF8字符集，這個可以賦予了生命“NLS_LANG”為“AMERICAN_AMERICA.UTF8”，然后把重起pl/sqldeveloper。其它字符集設(shè)置同上