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MySQL 날짜 함수 같은데서 INTERVAL unit 으로 쓸 수 있는 것들 unit value Expected expr Format MICROSECOND MICROSECONDS SECOND SECONDS MINUTE MINUTES HOUR HOURS DAY DAYS WEEK WEEKS MONTH MONTHS QUARTER QUARTERS YEAR YEARS SECOND_MICROSECOND 'SECONDS.MICROSECONDS' MINUTE_MICROSECOND 'MINUTES:SECONDS.MICROSECONDS' MINUTE_SECOND 'MINUTES:SECONDS' HOUR_MICROSECOND 'HOURS:MINUTES:SECONDS.MICROSECONDS' HOUR_SECOND 'HOUR..

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..

오라클 DENSE_RANK() - 순위를 정하기 좋은 함수 같다. 그룹내에 정렬된 데이타의 순위를 매기기 좋은 함수 정도 ?? Aggregate Syntax 생략 Analytic Syntax DENSE_RANK() OVER(PARTION BY ~~~ ORDER BY ~~~) DENSE_RANK computes the rank of row in an ordered group of rows and returns the rank as a NUMBER. Then ranks are consecutive integers beginning with 1. The larget rank value is the number of unique values returned by the queyr. Rank values are ..