45. 資料欄位語法 ( 一 )
• 關於資料欄位的語法
select * from customer;
select name, addr, contact from
customer;
select name as n, addr as a contact
as c from customer;
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46. 資料欄位語法 ( 二 )
• 計算資料數量
select count(*) from customer;
• 剃除重複資料
select distinct addr from customer;
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50. 資料群組語法
• 關於資料群組的語法
select addr, count(addr) from
customer group by addr;
select addr, count(addr) from
customer group by addr having
count(addr)>2;
註:集合函數 count, sum, min, max, avg 常搭配群組語法一併使用
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Windows 組態設定精靈 : Developer -> Multifunctional -> OLAP -> add firewall exception -> Best Support For Multilingualism -> check Include Bin Directory in Windows PATH -> Set password -> check Enable root access -> Execute