Oracle's Single-line functions: Character functions

Character function

1.ASCII (x) and Chr (x)

ASCII (x): Returns the ASCII code for the character X

Chr (x): Returns a character with an ASCII code of X

2.concat (X,y)

Used to add Y to X after, with | | function as

3.initcap (x)

Converts the first letter of each word in X to uppercase

4.instr (X,find_string[,start][,occurence])

Find find_string in X, return the location of find_string

Optional parameter start: Describes where to start looking from X, the first position is 1.

Optional parameter occurence: Description should return the first occurrence of find_string

5.length (x) and LENGTHB (x)

Length (x): Returns the number of characters in X

LENGTHB (x): Returns the number of bytes in X

6.lower (x) and upper (X)

Lower (x): Converts letters in x to lowercase, non-letter conversions

Upper (x): Converts letters in X to uppercase

7.lpad (x, Width [, pad_string]) and Rpad (X,width[,pad_string])

Lpad (x, Width [, pad_string]): Used to make the left of x blank space, so that the total length reached the width of the characters

Optional parameter pad_string: If given, the left of X is padded pad_string character

Rpad (X,width[,pad_string]): For the right of x to padded space, so that the total length of the width of the characters

Optional parameter pad_string: If given, the right of X is padded with pad_string characters

8.ltrim (x[,trim_string]), RTrim (x[,trim_string]) and trim (x[,trim_string))

LTrim (x[,trim_string]): Used to truncate some spaces from the left side of X

Optional parameter trim_string: If given, truncate some trim_string characters from the left side of X

RTrim (x[,trim_string]): Used to truncate some spaces from the right side of X

Optional parameter trim_string: If given, the trim_string characters are truncated from the right of X

Trim (x[,trim_string]): Used to truncate some spaces from the left and right sides of X

Optional parameter trim_string: If given, cut some trim_string characters from the left and right sides of X

9.NVL (X,value) and NVL2 (x,value1,value2)

NVL (X,value): is used to convert a null value to a known value, and if x is null, return value, otherwise return x

NVL2 (x,value1,value2): Determines whether x is null, if x is not empty, returns VALUE1, otherwise returns value2

10.replace (x,search_string,repalce_string)

Used to find search_string in X and replace it with replace_string

11.soundex (x)

Used to get a string containing the x pronunciation that is used to compare words that are different in spelling but have a similar pronunciation

12.substr (X,start[,length])

Used to get a substring from the start position from X

Optional parameter length: Specifies the length of the substring, if not given, until the end of the string

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