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MySQL vs MySQLi when using PHP [closed]
...It should also be noted that MySQLi only works with MySQL 5+. This isn't really relevant anymore, but when MySQLi came out, MySQL 4 was still the standard. This is part of the reason the extensions are separate, the old MySQL driver staying there for compatibility purposes.
– z...
Application Loader: “Cannot proceed with delivery: an existing transporter instance is currently upl
...
Basically, you need to clear out the transport tokens. This can happen if you were to close out of Xcode while in the middle of submitting an app to iTunes Connect.
The token files now appear in the
Library/Caches/com.apple.amp.i...
Comparing Dates in Oracle SQL
...; to_date('31-DEC-95','DD-MON-YY')
This method has a few unnecessary pitfalls
As a_horse_with_no_name noted in the comments, DEC, doesn't necessarily mean December. It depends on your NLS_DATE_LANGUAGE and NLS_DATE_FORMAT settings. To ensure that your comparison with work in any locale you can u...
What is the purpose of the '@' symbol in CSS?
...ructs. The @ syntax itself, though, as I mentioned, is not new.
These are all known in CSS as at-rules. They're special instructions for the browser, not directly related to styling of (X)HTML/XML elements in Web documents using rules and properties, although they do play important roles in control...
What's the fastest way to merge/join data.frames in R?
...(y) from main.d group by g1, g2"))
)
The outputs from the two benchmark call comparing the merge calculations are:
Joining by: x
test replications elapsed relative user.self sys.self user.child sys.child
3 data.table 1 0.34 1.000000 0.31 0.01 NA NA
2 ...
Why does direction of index matter in MongoDB?
...d query in the same order as the index will simply return the rows sequentially in the correct order.
Finding a record in a BTree takes O(Log(n)) time. Finding a range of records in order is only OLog(n) + k where k is the number of records to return.
If the records are out of order, the cost coul...
Do you have to put Task.Run in a method to make it async?
... numbers for the sake of this example, granted, it's no processing time at all, it's just a matter of formulating an example here.
...
Equivalent of varchar(max) in MySQL?
... includes a byte or two to encode the length of a given string. So you actually can't declare a varchar of the maximum row size, even if it's the only column in the table.
mysql> CREATE TABLE foo ( v VARCHAR(65534) );
ERROR 1118 (42000): Row size too large. The maximum row size for the used tabl...
Why does my application spend 24% of its life doing a null check?
...t store a copy of the bytes in RAM. An important one is the L1 cache, typically 16 kilobytes for data and 16 kilobytes for instructions. Small, allowing it to be close to the execution engine. Reading bytes from the L1 cache typically takes 2 or 3 CPU cycles. Next up is the L2 cache, bigger and slow...
What is the difference between '>' and a space in CSS selectors?
...o scenarios div > span { } vs. div span { }
Here, the (space) selects all the all the <span> elements inside <div> element even if they are nested inside more than one element. The > selects all the children of <div> element but if they are not inside another element.
Take...