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Explanation of the meaning of common PHP error prompts (practical! Worth collecting), error prompts are worth collecting

This article explains the meaning of common PHP error prompts. Share it with everyone for your reference, the details are as follows:

When I was learning PHP, I often encountered various error prompts. It felt good to see this error prompt and explanation today. I now turn it over for us to learn from. hehe. . . . .

1. Notice: Undefined variable: variable name in
Note: An undefined variable is used

2. Parse error: syntax error, unexpected T_ELSE in
If () {
}Else if () {
}
Echo $test;
Else {
}
Note: The if else if else sentence structure is wrong

3. Parse error: syntax error, unexpected $end in D
Note: Usually the curly braces do not match

4. Parse error: syntax error, unexpected T_STRING in
Note: Usually I forget to write the semicolon at the end of the sentence

5. Warning: Invalid argument supplied for foreach() in
Note: the first parameter of foreach must be an array

6. Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in
Note: This means that the previous execution of SQL failed to return. Generally, it may be an error in the SQL statement. If the analysis cannot come out, you can just print out Mysql_error (); to see where the error is specifically

7. No database selected
Note: Usually there is no connection to the database

8. Warning: mysql_connect() [function.mysql-connect]: Access denied for user 'root'@'localhost' (using password : YES) in ….. on line 3
Access denied for user
'root'@'localhost' (using password: YES)
Note: The database username and password are wrong

9. Unknown database 'cms07261′
Note: There is no such database

10. Table 'cms0726.test' doesn't exist
Note: The table does not exist

11. Unknown column 'abc' in 'field list'
Note: Field does not exist

12. Column count doesn't match value count at row 1
Note: The number of field values ​​in the sql statement is different from the number of field names

13. Warning: Wrong parameter count for function name in
Note: The number of function logarithms is missing

14. Fatal error: Smarty error: [in message_list.html line 22]: syntax error: 'foreach: item' must be a variable name (literal string)
Note: Look at the line number, it means that the item after foreach must be followed by a variable name, without $, it is a string (note: no single or double quotes)

15. Fatal error: Smarty error: [in message_list.html line 24]: syntax error: unrecognized tag: msg.message_id
Note: $

is missing before the variables in the template

16. Warning: Smarty error: unable to read resource: "message_list1.html" in
Note: The template file cannot be found. Check whether the file name is written incorrectly or the file is stored in another directory.

17. Fatal error: Cannot redeclare get_sort1() (previously declared in
Note: The function has been defined and cannot be redefined

I hope this article will be helpful to everyone in PHP programming.

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