Oracle-Decode()函數和CASE語句的區別: 具體樣本如下: 1.CASE語句: SELECT CASE SIGN(5 - 5) WHEN 1 THEN 'Is Positive' WHEN -1 THEN 'Is Negative' ELSE 'Is Zero' END FROM DUAL; 後台實現: if (SIGN(5 – 5) = 1) { 'Is Positive'; } else if (SIGN(5 – 5) = 2 ) {
方法一今天想在預存程序比較兩個字元,但發現沒有得到預期的結果,最主要是一個問題:任何值和null比較得到的結果都是null,在網上找到了兩種方法,供大家參考一下在ORACLE中,將Null 字元串視為NULL,任何值與NULL比較結果都為NULL。如此一來,在比較兩個字串的時候就會出現意外。請看以下的例子:DECLARE i VARCHAR2(10) := NULL; v VARCHAR2(10) := 'ABC';BEGIN IF(i = v) THEN
DECODEDECODE( 1 1 2 2)IF THEN RETURN() IF THEN RETURN() ELSE RETURN()NVLNVL(EXPR1,EXPR2) EXPR1NULL,EXPR2,EXPR1. Substr的格式:substr('This is a test', 6, 2) would return 'is'substr('This is a test', 6)
1.----查某session當前正在執行的sqlSQL>select s.sid,sql_text from v$session s,v$sql qwhere s.SQL_ADDRESS=q.address and s.sql_hash_value=q.hash_valueand s.sid in (45,48,107) and s.serial# in (53098,54004,44803);SQL>select p.spid,sql_text from v$sqlarea
首先用作業系統命令找出CPU利用率較高的進程ID1.查看資料庫當前執行的所有SQL和對應的進程IDcolumn machine format a16;column program format a16;select p.spid,s.status,s.machine,p.program,q.sql_textfrom v$session s,v$sqlarea q,v$process pwhere s.sql_address=q.address and
看了很多CodeSmith2.6的關於Oracle Provider的文章。很少看到 CodeSmith3.0關於此的,昨天實驗了一下。進入CodeSmith的Community,http://community.codesmithtools.com/files/9/schemaproviders/default.aspx,在這個文件夾中有一個Oracle Schema Provider,下載下來,按照說明:To "install" the provider, just copy the
轉自:http://www.cnblogs.com/ruanbl/archive/2008/02/29/1086398.htmlEXTRACT extracts and returns the value of a specified datetime field from a datetime or interval value expression.The field you are extracting must be a field of the datetime_value_expr