ORACLE： - 首先選擇名稱，由第一個字後，除去空間

Question

ORACLE： - 在表中的第一名稱如下

Binda E                    
Reven O                    
Drew J            
ANDAL J                      
WILL Lee            
Chad Hardee 

我要在以下格式來選擇名字

Binda                    
Reven                     
Drew            
ANDAL                       
WILL            
Chad 

我使用下面的查詢，但沒有運氣

SELECT first_name, SUBSTR(first_name, REGEXP_INSTR('first_name','[^ ]+', 1, 1)) FROM contact.user_names 

請蘇ggest。

Answer 1

NVL（SUBSTR（如first_name，1，INSTR（如first_name，」 '）），如first_name）

with t AS 
    (
    SELECT 'Binda E ' as first_name FROM dual                   
    union 
    SELECT 'Reven O ' as first_name FROM dual                    
    union 
    SELECT 'Drew J ' as first_name FROM dual           
    union 
    SELECT 'ANDAL J ' as first_name FROM dual                     
    union 
    SELECT 'WILL Lee ' as first_name FROM dual           
    union 
    SELECT 'Chad Hardee' as first_name FROM dual 
    union 
    SELECT 'foobar' as first_name FROM dual 

    ) 
    SELECT NVL(substr(first_name, 1, instr(first_name,' ')), first_name) FROM t 
    ;