There are 4 functions that can remove spaces: 1. The replace() function can replace the spaces in the string with null characters to remove all spaces. The syntax is "replace(string,' ',' ')"; 2. The trim() function can remove the spaces at the beginning and end of the string, the syntax is "TRIM(string)"; 3. The LTRIM() function can remove the spaces on the left side of the string, the syntax is "LTRIM(string)" )"; 4. The RTRIM() function can remove the spaces on the right side of the string, the syntax is "RTRIM(string)".
The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.
There are several commonly used methods to clear string spaces in mysql:
One is to use the trim function, which has two branches: LTRIM and RTRIM functions
The other is to directly replace the character replacement function to clear it
1. Use the mysql replace function to remove spaces
Syntax: replace(object,search,replace)
Meaning: Replace all occurrences of search in object with replace
Case: Clear news Spaces in the content field in the table
update `news` set `content`=replace(`content`,' ','');
Note: The replace function can also be used to remove a certain character
Remove all specified ordinary characters in the string, such as: [
update table set column1= REPLACE(column1,'[','') ;
Remove all specified special characters in the string, such as: single quote ', please note that you need to use backslash\escaping
update table set column1= REPLACE(column1,'\'','') ;
2. Use the mysql trim function to remove leading and trailing spaces
Full format: TRIM([{BOTH | LEADING | TRAILING} [remstr] FROM] str)
Simplified format: TRIM([remstr FROM] str)
The following examples:
mysql> SELECT TRIM(' phpernote '); -> 'phpernote'
mysql> SELECT TRIM(LEADING 'x' FROM 'xxxphpernotexxx'); -> 'phpernotexxx'
mysql> SELECT TRIM(BOTH 'x' FROM 'xxxphpernotexxx'); -> 'phpernote'
3, Use the mysql LTRIM function to remove left spaces
Syntax: LTRIM(str)
Example:
mysql> SELECT LTRIM(' barbar'); -> 'barbar'
4 , use mysql RTRIM function to remove right spaces
Syntax: RTRIM(str)
Example:
mysql> SELECT RTRIM('barbar '); -> 'barbar'
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