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MySql Table Insert if not exist otherwise update
...ould not change. You do need to include all of the other columns from your table. You can use the VALUES() function to make sure the proper values are used when updating the other columns.
Here is your update re-written using the proper INSERT ... ON DUPLICATE KEY UPDATE syntax for MySQL:
INSERT I...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
...hese macros only helps the first time code is executed or when the history table is overwritten by a different branch with the same index into the branching table. In a tight loop, and assuming a branch goes one way most of the time, the branch predictor will likely begin guessing the correct branc...
What is the difference between user and kernel modes in operating systems?
... the application with a private virtual address space and a private handle table. Because an application's virtual address space is private, one application cannot alter data that belongs to another application. Each application runs in isolation, and if an application crashes, the crash is limited ...
Is C++14 adding new keywords to C++?
...
Table 4 (Keywords) in N3936 (C++14):
alignas continue friend register true
alignof decltype goto reinterpret_cast try
asm default ...
Rank function in MySQL
...itialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT INTO person VALUES (2, 'Jane', 20, 'F');
INSERT INTO person VALUES (3, 'Jack', 30, 'M');
INSERT IN...
Querying DynamoDB by date
...ndary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist within each hash key partition, thus requiring the hash key to also be specified when making the query.
For the use case in this question, you would want to...
Sequelize.js: how to use migrations and sync
...h and the database structure is going to change -- new columns in existing tables as well as new tables, and new associations to existing and new models.
...
Deprecated: mysql_connect()
...tical with the old way:
<?php
// Old way
mysql_query('CREATE TEMPORARY TABLE `table`', $connection);
// New way
mysqli_query($connection, 'CREATE TEMPORARY TABLE `table`');
Turn off all deprecated warnings including them from mysql_*:
<?php
error_reporting(E_ALL ^ E_DEPRECATED);
The Exac...
How to add spacing between UITableViewCell
Is there any way to add spacing between UITableViewCell ?
30 Answers
30
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Throw an error in a MySQL trigger
If I have a trigger before the update on a table, how can I throw an error that prevents the update on that table?
7 An...