SqlServer2008 Common functions

S: string parameter; d: integral type parameter; f:float type parameter

One, the string function

ASCII (' xxx ') returns the ASCII code of the leftmost character in the string, example: Select ASCII (' Charles ') returns the ASCII code of ' C '

char (' xxx ') converts the ASCII code to a character with a range of values 0~255

charindex (s1,s2[,d]) find S1 in S2, return first match position, cannot find return 0, have one null return NULL

difference (S1,S2) returns an integer value from 0 to 4 that indicates the similarity between two character expressions, and the larger the number, the more similar

Left (s,d) returns the specified number of characters in the string

Right (s,d) returns the specified number of characters in the string

Len (s) returns the number of characters of the specified string expression, with no trailing spaces

Lower (s) returns a lowercase string

Upper (s) returns an uppercase string

LTrim (s) returns a string that removes the opening space

RTrim (s) returns a string that removes the trailing space

patindex (S1,S2) returns the position of S1 that appears in S2, no return 0;s1 can have wildcards,%: any number of characters; _: any one character

reverse (s) returns the new string after the specified string is reversed

Space (d) returns the specified number of spaces

str (F[,D1[,D2]]) float number is converted to a string, D1 represents the total length of the string, D2 represents the number of digits retained after the decimal point. Returns the number of characters less than the total length of the preceding fill space, which exceeds the total length of the truncated decimal place. Returns * * If truncation of integer digits is required. Rounding is followed when truncating. The total length includes decimal points, symbols, numbers, and spaces. The default value is 10. Retain up to 16 digits after the decimal point, the number after the decimal point is not preserved by default

Stuff (S1,D1,D2,S2) deletes the S1 string from the D1 position d2 length, adding S2 string, example: Select Stuff (' abcdef ', 2, 2, ' 123 ') return A123def

substring (S,D1,D2) returns the length of the string s from the D1 position, starting at D2. Example: Select substring (' abcdef ', 2,2) returns BC

Replace (S1,S2,S3) returns the new string after replacing all occurrences of the S2 string in the S1 string with S3. Example: Select replace (' ABCTTABCHHABC ', ' abc ', ' 123 ') returns 123tt123hh123

Reprint: http://blog.csdn.net/travylee/article/details/7216481

SqlServer2008 Common functions