MySQL Text Function

 

For preforming the operations on strings, MySQL has provided some function:

1. UCASE ()/UPPER () 

It converts all characters in the specified string to uppercase. If there are characters in the string that are not letters, they are unaffected by this function.

Syntax:

UCASE( string )

Parameter or Arguments:

string: The string to convert to uppercase.

2. LCASE ()/LOWER ()

It converts all characters in the specified string to lowercase. If there are characters in the string that are not letters, they are unaffected by this function.

Syntax:

LCASE( string )

Parameter or Arguments:

string: The string to convert to lowercase.

3. MID ()/SUBSTRING ()/SUBSTR () 

This function allows you to extract a substring from a string.

Syntax:

MID( string, start_position, [length] )

SUBSTR( string, start_position, [ length ] )

SUBSTRING( string, start_position, [ length ] )

Parameter or Arguments:

string: The string from which Substring is required.

start_position: The position to begin extraction. The first position in the string is always 1.

Length: The number of characters to extract

4. LENGTH ()

This function returns the length of the specified string (measured in bytes).

Syntax:

LENGTH( string )

Parameter or Arguments:

string: The string to return the length for.

5. LEFT ()

LEFT function allows you to extract a substring from a string, starting from the left-most character.

Syntax:

LEFT( string, number_of_characters )

Parameter or Arguments:

string: The string that you wish to extract from.

number_of_characters: The number of characters that you wish to extract from a string starting from the left-most character.

6. RIGHT ()

The RIGHT function allows you to extract a substring from a string, starting from the right-most character.

Syntax:

RIGHT( string, number_of_characters )

Parameter or Arguments:

string: The string that you wish to extract from.

number_of_characters: The number of characters that you wish to extract from a string starting from the right-most character.

7. INSTR ()

INSTR function returns the location of a substring in a string.

Syntax:

INSTR( string, substring )

Parameter or Arguments:

string: The string to search.

substring: The substring to search for in string.

8. LTRIM ()

LTRIM function removes all space characters from the left-hand side of a string.

Syntax:

LTRIM( string )

Parameter or Arguments:

string: The string to trim the space characters from the left-hand side.

9. RTRIM ()

RTRIM function removes all space characters from the right-hand side of a string.

Syntax:

RTRIM( string )

Parameter or Arguments:

string: The string to trim the space characters from the right-hand side.

10. TRIM ()

TRIM function removes all specified characters either from the beginning or the end of a string.

Syntax:

TRIM( [ LEADING | TRAILING | BOTH ] [ trim_character FROM ] string )

Parameter or Arguments:

LEADING: Optional. Removes the trim_character from the front of the string.

TRAILING: Optional. Removes the trim_character from the end of the string.

BOTH: Optional. Removes the trim_character from the front and end of string.

trim_character: Optional. The character that will be removed from the string. If this parameter is omitted, it will remove space characters from the string.

string: The string to trim.