개인적인 정리

오라클 REGEXP_REPLACE() REGEXP_REPLACE() - REGEXP_REPLACE(source_char, pattern, replace_string) REGEXP_REPLACE(source_char, pattern, replace_string, position, occurence, match_param) 의 형태 가 있다.

오라클 REGEXP_INSTR() REGEXP_INSTR() - REGEXP_INSTR(source_char, pattern) REGEXP_INSTR(source_char, pattern, position, occurence, return_opt, match_prarm, subexpr) 의 형태 REGEXP_INSTR extends the functionality of the INSTR function by letting you search a string for a regular expression pattern. The function evaluates string using characters as defined by the input character set. It returne an intege..

오라클 REGEXP_COUNT() REGEXP_COUNT() - REGEXP_COUNT(source_char, pattern) REGEXP_COUNT(source_char, pattern, position, match_param) 의 형태 REGEXP_COUNT complements the functionality of the REGEXP_INSTR function by returning the number of times a pattern occurs in a source string. The function evaluates strings using characters as defined by the input character set. It retruns and integer indicating t..

오라클 RAWTOHEX() RAWTOHEX() - RAWTOHEX(raw) 의 형태 RAWTOHEX converts raw to a character value containing its hexadecimal representation. As a SQL built-in function, RAWTOHEX accepts an argument of any scalar data type other than LONG, LONG RAW, CLOB, BLOB, or BFILE. It returns a VARCHAR2 value with the hexadecimal representation of bytes that make up the value of raw. Each byte is represented by two..

오라클 RATIO_TO_REPORT() RATIO_TO_REPORT() - 합계에서 각 row가 차지하는 비율을 구할 때 좋은 것 같다. RATIO_TO_REPORT(expr) OVER(query_partition_clause) 의 형태 RATIO_TO_REPORT is an analytic function. It computes the ratio of a value to the sum of a set of values. If expr evaluates to null, then the ratio-to-report value also evaluates to null. The set of values is determined by the query_partion_clause. If you omit that ..

오라클 RANK() RANK() - RANK(expr) WITHIN GROUP (ORDER BY expr DESC|ASC NULLS FIRST|LAST) RANK() OVER (query_partition_clause order_by_clause) 의 형태 RANK calculates the rank of a value in a group of values. The return type is NUMBER. Rows with equal values for the ranking criteria receive the same rank. Oracle Database then adds the number of tied rows to the tied rank to calculate the next rank. The..

오라클 POWER() POWER() - 제곱에 대한 표현 POWER(n2, n1) 의 형태 POWER returns n2 raised to the n1 power. The n2 and the exponent n1 can be any numbers, but if n2 is negative, then n1 must be an integer. This function takes as arguments any numeric data type or any nonnumeric data type that can be implicitly converted to a numeric data type. If any argument is BINARY_FLOAT or BINARY_DOUBLE, then the function ..

오라클 PERCENT_RANK() PERCENT_RANK() - PERCENT_RANK(expr) WITHIN GROUP(ORDER BY expr DESC|ASC NULLS FIRST|LAST) PERCENT_RANK() OVER (query_partition_clause order_by_clause) 의 형태 PERCENT_RANK is similar to the CUME_DIST(cumulative distribution) function. The range of values returned by PERCENT_RANK is 0 to 1. inclusive. The first row in any set has a PERCENT_RANK of 0. The return value is NUMBER. As..