PHP MYSQLI计数行正确[删除]

Question

Table

Hello i try to finds all hashtags with name #c3 and mysqli query show me: 3 rows but correct is 2 rows with #c3 ??? where is problem ? I want to show me 2Rows !

$sql_query = mysqli_query($Connection, "SELECT * FROM my_table WHERE hashtag LIKE '%#c3%'");
echo mysqli_num_rows($sql_query);

Answer 1

To answer this and as left in comments (by myself)

Use '%#c3' by removing the last %

Using LIKE, the % wildcard does the following and a few examples:

%XXX% - Matches anything before and after XXX

%XXX - Matches anything before XXX

XXX% - Matches anything after XXX.

References:

• http://dev.mysql.com/doc/refman/5.7/en/string-comparison-functions.html
• http://dev.mysql.com/doc/refman/5.7/en/pattern-matching.html
• http://www.tutorialspoint.com/mysql/mysql-like-clause.htm

Plus, should there be any user input, consider using a prepared statement:

• https://en.wikipedia.org/wiki/Prepared_statement

It will help against a potential SQL injection.

• https://en.wikipedia.org/wiki/SQL_injection