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오라클 INITCAP() INITCAP() - INITCAP(char) 의 형태 INITCAP returns char, with the first letter of each word in uppercase, all other letters in lowercase. Words are delimited by white space or characters that are not alphanumeric. char can be of any of the data type CHAR, VARCHAR2, NCHAR, or NVARCHAR2. The return value is the same data type as char. The database set the case of the initial characters b..

오라클 GROUP_ID() GROUP_ID() - grouping 할 때... group_id 를 숫자로 부여. - 음... 처음보지만 필요한 함수다. GROUP_ID() 의 형태 GROUP_ID distinguishes duplicate groups resulting from a GROUP BY sepcification. It is useful in filtering out duplicate groupings from the query result. It returns an Oracle NUMBER to uniquely identify duplicate groups. This function is applicable only in a SELECT statement that contains a GROUP..

오라클 GREATEST() GREATEST returns the greatest of a list of one more expressions. Oracle Database uses the first expr to determine the return type. If the first expr is numeric, then Oracle determines the argument with the highest numeric precedence, implicitly converts the remaining arguments to that data type before the comparsion, and returns that data type. If the first expr is not numeric, th..

오라클 FLOOR() FLOOR(n) FLOOR returns the largest integer equal to or less than n. The number n can always be written as the sum of an integer k and a positive fraction f such that 0 SELECT FLOOR(15.7) FROM DUAL ; --> 15

오라클 FIRST() 이런 함수가 있는지 처음 알았다. FIRST AND LAST are very similar functions. Both are aggregate and analytic functions that operate on a set of values from a set of rows that rank as the FIRST or LAST with respect to a given sorting specification. If only row ranks as FIRST or LAST, then the aggregate operates on the set with only one element. If you omit the OVER caluse, then the FIRST and LAST fu..

오라클 EXTRACT() EXTRACT(datetime_filed FROM expr) datetime_field 에는 YEAR, MONTH, DAY, HOUR, MINUTE, SECOND, TIMEZONE_HOUR, TIMEZONE_MINUTE, TIMEZONE_REGION, TIMEZONE_ABBR 이 올 수 있다. EXTRACT extracts and returns the value of a specified datetime field from a datetime or interval expression. The expr can be any expression that evaluates to a datetime or interval data type compatible with the request ..

오라클 EXP() 지수함수 정도 ? EXP returns a raised to the nth power, where e=2.71828183... . The function returns a value of the same type as the argument. This function takes as an argument any numeric data type or any nonnumeric data type that can be implicitly converted to a numeric data type. If the argument is BINARY_FLOAT, then the function returns BINARY_DOUBLE. Otherwise the functionk returns the ..

오라클 EMPTY_BLOB() 오라클 EMPTY_CLOB() EMPTY_BLOB and EMPTY_CLOB return an empty LOB locator that can be used to initialize a LOB variable or, in an INSERT or UPDATE statement, to initialize a LOB column or attribute to EMPTY. EMPTY means that the LOB is initialized, but not populated with data. An empty LOB is not the same as null LOB, and an empty CLOB is not the same as a LOB containing a string o..