NULL values fail comparisons both with < and with >= : String Compare « String « SQL / MySQL

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SQL / MySQL » String » String Compare 
NULL values fail comparisons both with < and with >=
      
mysql>
mysql> CREATE TABLE mytable
    -> (
    ->  name    CHAR(20),
    ->  id              CHAR(20)
    -> );
Query OK, rows affected (0.00 sec)

mysql> INSERT INTO mytable (name,idVALUES ('Tom','198-48');
Query OK, row affected (0.00 sec)

mysql> INSERT INTO mytable (name,idVALUES ('Jack',NULL);
Query OK, row affected (0.00 sec)

mysql> INSERT INTO mytable (name,idVALUES ('Mary',NULL);
Query OK, row affected (0.00 sec)

mysql> INSERT INTO mytable (name,idVALUES ('Jane','475-83');
Query OK, row affected (0.00 sec)

mysql>
mysql>
mysql> SELECT FROM mytable WHERE id >= '200-00' OR id IS NULL;
+------+--------+
| name | id     |
+------+--------+
| Jack | NULL   |
| Mary | NULL   |
| Jane | 475-83 |
+------+--------+
rows in set (0.00 sec)

mysql>
mysql> drop table mytable;
Query OK, rows affected (0.00 sec)

mysql>

   
    
    
    
    
    
  
Related examples in the same category
1.Compare String in where clause
2.String comparisons are performed from left to right, one character at a time:
3.The two strings '4200' and '4200.0' are not the same:
4.Case-insensitive nature of string comparisons:
5.String comparisons in MySQL are not case sensitive by default:
6.To make a string comparison case sensitive, cast (convert) one of the strings to binary form by using the BINA
7.To make a string comparison not case sensitive, convert both strings to the same lettercase using UPPER( ) or
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