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오라클 DELETEXML(); DELETEXML deletes the node or nodes matched by the XPATH expression the the target XML.

오라클 DECODE() DECODE(expr, search, result, default) DECODE(expr, search, result, search, result, search, result, default); 와 같은 형태도 가능하여 여러개를 한번에 비교할 수 있다. DECODE compares expr to each search value one by one. If expr is equals to a search, then Oracle Database returns the corresponding result. If no match is found, then Oracle returns default. If default is omitted, then Oracle returns null. The..

오라클 CURRENT_TIMESTAMP() CURRENT_TIMESTAMP(precision) CURRENT_TIMESTAMP returns the current date and time in the session time zone, in a value of data type TIMESTAMP WITH TIME ZONE. The time zone offset reflects the current local time of SQL session. If you omit precision, then the default is 6. The difference between this function and LOCALTIMESTAMP is the CURRENT_TIMESTAMP returns a TIMESTAMP W..

오라클 CURRENT_DATE() CURRENT_DATE returns the current date in the session time zone, in a value in the Gregorian calendar of data type DATE. SQL > SELECT SESSIONTIMEZONE, CURRENT_DATE FROM DUAL ; --> +09:00 2020/03/26 오전 10:40:48

오라클 COUNT() COUNT returns the number of rows returned by the query. You can use it as an aggregate or analytic function If you specity DISTINCT, then you can sepcify only the query_partition_clause of the analytic_clause. The order_by_clause and windowing_clause are not allowed. If you speify expr. then COUNT returns the number of rows where expr is not null. You can count either all rows, or on..

오라클 cos() COS returns the cosine of n (an angle expressed in radians). 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 return BINARY_DOUBLE. Otherwise the function returns the same numeric data type as the argument. SQL > SELECT COS(180* 3.14159265359) ..

오라클 CONCAT() -오라클에서 문자열을 이어붙일 수 있는 함수 CONCAT(char1, char2) CONCAT returns char1 concatenated with char2. Both char1 and char2 can be any of the data types CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB or NCLOB. The string returned is in the same character set as char1. Its data type depends on the data types of the arguments. In concatenations of two different data types, Oracle Database returns the da..

오라클 COLLECT() COLLECT is an aggregate function that takes as its argument a column of any type and creates a nested table of the input type out of the rows selected. Te get accurate results form this function you must use it within a CAST function. 아래 예제를 확인해볼려면 오라클에서 oe 계정을 활성화시켜야 한다. SQL> ATLER USER OE ACCOUNT UNLOCK ; SQL> ATLER USER OE IDENTIFIED BY 'OE12345678' ; SQL> SELECT COLLECT(warehou..