PL/SQL single-row functions and group functions (2)

Single-row numeric Functions

A single-row numeric function operates on numeric data and performs mathematical and arithmetic operations. All functions have numeric parameters and return numeric values. The operands and values of all trigonometric functions are radians rather than degrees. Oracle does not provide built-in radians and angle conversion functions.

　　ABS ( )
Returns the absolute value of N.

　　ACOs ( )
Returns the number between-1 and 1 in the anti-Yuxuan function. N indicates radians

Select ACOs (-1) PI, ACOs (1) zero from dual Pi zero 3.14159265 0

　　Asin ( )
Returns-1 to 1, and N to indicate radians.

　　Atan ( )
Returns the arc tangent value of N. N indicates radians.

　　Ceil ( )
Returns the smallest integer greater than or equal to n.

　　Cos ( )
Returns the remainder Xuan value of N, and N is a radian.

　　Cosh ( )
Returns the hyperbolic remainder of n, where n is a number.

Select cosh (<1.4>) from dual Cosh (1.4) 2.15089847

　　Exp ( )
Returns the N power of E, E = 2.71828183.

　　Floor ( )
Returns the largest integer less than or equal to n.

　　Ln ( )
Returns the natural logarithm of N. N must be greater than 0.

　　Log ( , )
Returns the base N2 logarithm of N1.

　　MoD ( )
Returns the remainder of N1 divided by N2,

　　Power ( , )
Returns the N2 power of N1.

　　Round ( , )
Return the value of N1 rounded to the right of the decimal point. The default value of N2 is 0. This is the nearest integer to the decimal point. If N2 is a negative number, it is rounded to the corresponding digit on the left of the decimal point, n2 must be an integer.

Select round (12345,-2), round (12345.54321, 2) from dual Round (12345,-2) round (12345.54321, 2) 12300 12345.54

　　Sign ( )
If n is negative,-1 is returned. If n is positive, 1 is returned. If n = 0, 0 is returned.

　　Sin ( )
Returns the positive and negative values of N, and N is a radian.

　　Sinh ( )
Returns the hyperbolic Xuan value of N, which is radian.

　　SQRT ( )
Returns the square root of N, and N is a radian.

　　Tan ( )
Returns the tangent of N. N is a radian.

　　Tanh ( )
Returns the hyperbolic tangent of N. N is a radian.

　　Trunc ( , )
Return the N1 value from the ending point to the N2 decimal point. The default value of N2 is 0. When N2 is the default value, the ending point of N1 is an integer. If N2 is a negative value, it is truncated at the right of the decimal point.

　　Single Row date functions

A single-row date function operates on data types. The vast majority of data type parameters are available, and the vast majority of returned data types are also values.

　　Add_months ( , <I>)
Returns the result after date D plus I months. I can make any integer. If I is a decimal point, the database implicitly converts it to an integer, and the part after the decimal point is truncated.

　　Last_day ( )
Returns the last day of the month containing the date D.

　　Months_between ( , )
Returns the number of months between D1 and D2. If the date of D1 and D2 is the same, or the last day of the month is used, an integer is returned, otherwise, the returned result contains a score.

　　New_time ( , , )
D1 is a date data type. When the date and time in Zone tz1 are d, the date and time in Zone tz2. Tz1 and tz2 are strings.

　　Next_day ( , )
Returns the first day of the condition given by Dow after the date D. Dow specifies a day in a week using the language given in the current session, and returns the same time component as the time component of D.

Select next_day ('01-Jan-2000 ', 'monday') "1st Monday", next_day ('01-Nov-2004', 'tuesday') + 7 "2nd Tuesday ") from dual; 1st Monday 2nd Tuesday 03-Jan-2000 09-nov-2004

　　Round ( [, ])
Round the date d in the format specified by FMT, and FMT is a string.

　　Syadate
The function has no parameters. The current date and time are returned.

　　Trunc ( [, ])
Returns the date D of the unit specified by FMT.