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ORACLE 에서 칼럼 값이 NULL 일 때 다른 값을 치환해주는 함수로 NVL 이 있다. 1 SELECT NVL(필드명, '널널') FROM 테이블명 ; cs * 필드명 대신에 다양한 표현식도 가능하다. 이전에 정리한 글이 있다. https://web-obj.tistory.com/429 [Oracle] NVL() 오라클 NVL() NVL() - NVL(expr1, expr2) 의 형태 NVL lets you replace null(returned as a blank) with a string in the results of a query. If expr1 is null, the NVL returns expr2. If expr1 is not null.. web-obj.tistory.com 예제) - NU..

오라클에서 컬럼 이름을 변경하는 방법 - RENAME COLUMN 을 사용한다. ALTER TABLE 테이블명 RENAME COLUMN 변경전 칼럼명 TO 변경후 칼럼명 ; ALTER TABLE TBL_NAME RENAME COLUMN AAAA TO BBBB ;

오라클 RTRIM() RTRIM() - RTRIM(char, set) 의 형태 RTRIM removes from the right end of char all of the characters that appear in set. This function is useful for formatting the output of a query. If you do not specify set, then it defaults to a single blank. If char is a character literal, then you must enclose it in single quotation marks. RTRIM works sililarly to LTRIM. Both char and set can be any o..

오라클 RPAD() RPAD() - RPAD(expr1, n, expr2) 의 형태 RPAD returns expr1, right-padded to length n characters with expr2, replicated as many times as necessary. This function is useful for formatting the output of a query. Both expr1 and expr2 can be any of the data types CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB, or NCLOB. The string returned is of VARCHAR2 data type, and a LOB if expr1 is a LOB data typ..

오라클 ROW_NUMBER() ROW_NUMBER() - ROW_NUMBER() OVER (query_partition_clause order_by_clause) 의 형태 ROW_NUMBER is an analytic function. It assigns a unique number to each row to which it is applied (either each row in the partition or each row returned by the query), in the ordered sequence of rows specified in the order_by_clause, beginning with 1. By nesting a subquery using ROW_NUMBER inside a qu..

오라클 ROUND(number) ROUND(number) - ROUND(n) ROUND(n, integer) 의 형태 ROUND returns n rounded to integer places to the right of the decimal point. If you omit integer, then n is rounded to zero places. If integer is negative, then n is rounded off to the left of the decimal point. n can be any numeric data type or any nonnumeric data type that can be implicitly converted to a numeric data type. If y..

오라클 ROUND(date) ROUND(date) - ROUND(date) ROUND(date, fmt) 의 형태 ROUND returns date rounded to the unit specified by the format model fmt. The function is not sensitive to the NLS_CALENDAR session parameter. It operates according to the rules of the Gregorian calendar. The value returned is always of data type DATA, even if you specify a different datetime data type for date. If you moit fmt, the..

오라클 REPLACE REPLACE() - REPLACE(char, search_string) REPLACE(char, search_string, replacement_string) 의 형태 REPLACE returns char with every occurence of search_string replaced with replacement_string. If replacement_string is omitted or null, then all occurence of search_string are removed. If search_string is null, then char is returned. Both search_string and replacement_string, as well as char..