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Cast from VARCHAR to INT - MySQL
...NED [INTEGER]
TIME
UNSIGNED [INTEGER]
Therefore, you should use:
SELECT CAST(PROD_CODE AS UNSIGNED) FROM PRODUCT
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Difference between 'struct' and 'typedef struct' in C++?
...different categories of identifiers, including tag identifiers (for struct/union/enum) and ordinary identifiers (for typedef and other identifiers).
If you just said:
struct Foo { ... };
Foo x;
you would get a compiler error, because Foo is only defined in the tag namespace.
You'd have to dec...
Insert auto increment primary key to existing table
...etrieve it by id immediately, MySQL offers LAST_INSERT_ID() for that value SELECT * FROM table_name WHERE id = LAST_INSERT_ID() and most programming language APIs offer some function/method to return that value in the application code.
– Michael Berkowski
Jan 2...
MySQL select with CONCAT condition
...available within the query itself.
You can either repeat the expression:
SELECT neededfield, CONCAT(firstname, ' ', lastname) as firstlast
FROM users
WHERE CONCAT(firstname, ' ', lastname) = "Bob Michael Jones"
or wrap the query
SELECT * FROM (
SELECT neededfield, CONCAT(firstname, ' ', last...
How to define a custom ORDER BY order in mySQL
...in the order you specify.
The second will involve a case somewhere, i.e.
SELECT * FROM table
ORDER BY CASE Language
WHEN 'ENU' THEN 3
WHEN 'JPN' THEN 2
WHEN 'DAN' THEN 1
ELSE 0
END DESC, ID ASC
Performance-wise the ENUM method will return faster results, but be more hassle if you...
Referring to a Column Alias in a WHERE Clause
...
SELECT
logcount, logUserID, maxlogtm,
DATEDIFF(day, maxlogtm, GETDATE()) AS daysdiff
FROM statslogsummary
WHERE ( DATEDIFF(day, maxlogtm, GETDATE() > 120)
Normally you can't refer to field aliases in the WHERE clau...
MySQL: Invalid use of group function
..., not WHERE.
The difference is: the WHERE clause filters which rows MySQL selects. Then MySQL groups the rows together and aggregates the numbers for your COUNT function.
HAVING is like WHERE, only it happens after the COUNT value has been computed, so it'll work as you expect. Rewrite your subque...
Maximum execution time in phpMyadmin
..._time = 5000
max_input_time = 5000
memory_limit = 1000M
And change xampp\mysql\bin\my.ini
max_allowed_packet = 200M
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How to get ER model of database from server with Workbench
...
Go to "Database" Menu option
Select the "Reverse Engineer" option.
A wizard will be open and it will generate the ER Diagram for you.
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MySQL, better to insert NULL or empty string?
...or an empty string using a bound variable but not for a NULL. This query:
SELECT *
FROM mytable
WHERE mytext = ?
will never match a NULL in mytext, whatever value you pass from the client. To match NULLs, you'll have to use other query:
SELECT *
FROM mytable
WHERE mytext IS NULL
...