# 2020金象盃 大數據 教學範例 > [name=Junter.wjs,] 作者：JunterTW 翻譯：XiangOuO ## 語法 #### ==[將資料載入變數]== 變數 = LOAD '資料集' USING PigStorage as (欄位:型態); > 範例 ```sql data = LOAD '/dataset/999004/999004.tsv' USING PigStorage ('\t') as (userid:chararray,gender:chararray,age:int,country:chararray,registered:chararray); ``` #### ==[查詢資料表Schema]== describe 變數; > 範例 ```sql describe data; ``` #### ==[顯示資料]== dump 變數; > 範例 ```sql dump data; ``` #### ==[查詢特定欄位] / [FOREACH] 取的每一筆資料== 變數 = FOREACH 變數 GENERATE 欄位; > 範例 ```sql data1 = FOREACH data GENERATE userid; /*[FOREACH] 取的每一筆資料 ``` #### ==[新增欄位]== 變數 = FOREACH 變數 GENERATE 欄位,999; > 範例 ```sql data1 = FOREACH data GENERATE userid,999; ``` #### ==[欄位轉型]== 變數 = FOREACH 變數 GENERATE (型態)$0; > 範例 ```sql data1 = FOREACH data GENERATE (chararray)$0,$1,$2; ``` #### ==[欄位重新命名]== 變數 = FOREACH 變數 GENERATE $0 as 欄位名稱; > 範例 ```sql data1 = FOREACH data GENERATE userid , gender ,$2 as number; ``` #### ==[欄位重新命名與轉型]== 變數 = FOREACH 變數 GENERATE $0 as 欄位名稱:型態; > 範例 ```sql data1 = FOREACH data GENERATE $0 as userid:chararray , $1 as gender:chararray; ``` #### ==條件過濾 / 語法== 變數 = FILTER 變數 BY (條件); 變數 = FILTER 變數 BY 欄位 MATCHES 正則表示法; > 範例 ```sql data1 = FILTER data BY (gender == 'f'); data1 = FILTER data BY country MATCHES 'B[A-Za-z0-9]*' B開頭所有字 ``` #### ==群組資料 / 語法== 變數 = GROUP 變數 BY 欄位; 變數 = GROUP 變數 ALL; > 範例 ```sql data1 = GROUP data BY country; data1 = GROUP data All; ``` --- :::warning :loudspeaker: 程式碼如有錯誤！請自行修正或聯絡我們。 :email: 4a990025@stust.edu.tw / c109181108@nkust.edu.tw ::: ###### Tags: `範例` `教學`