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Cannot change column used in a foreign key constraint
... DELETE ) will wait till timeout or UNLOCK TABLES; is executed
http://dev.mysql.com/doc/refman/5.5/en/lock-tables.html
EDIT 2: OP asked for a more detailed explanation of the line "The type and definition of foreign key field and reference must be equal. This means your foreign key disallows chang...
What is time_t ultimately a typedef to?
...
[root]# cat time.c
#include <time.h>
int main(int argc, char** argv)
{
time_t test;
return 0;
}
[root]# gcc -E time.c | grep __time_t
typedef long int __time_t;
It's defined in $INCDIR/bits/types.h ...
B-Tree vs Hash Table
In MySQL, an index type is a b-tree, and access an element in a b-tree is in logarithmic amortized time O(log(n)) .
5 Answ...
How to repair a serialized string which has been corrupted by an incorrect byte count length?
...
The OP's question does not appear to have a mysql column type issue. It is apparently corrupted by an incorrect byte calculation on the image value. Your answer does not pertain to the OP's specific question. You may wish to move your advice to: stackoverflow.com/q...
When NOT to use yield (return) [duplicate]
...ublic static IEnumerable<T> PreorderTraversal<T>(Tree<T> root)
{
if (root == null) yield break;
yield return root.Value;
foreach(T item in PreorderTraversal(root.Left))
yield return item;
foreach(T item in PreorderTraversal(root.Right))
yield return ...
How to make Sequelize use singular table names
...ames
freezeTableName: true
}
}
var sequelize = new Sequelize('mysql://root:123abc@localhost:3306/mydatabase', opts)
Now when you define your entities, you don't have to specify freezeTableName: true:
var Project = sequelize.define('Project', {
title: Sequelize.STRING,
descrip...
How do I put an 'if clause' in an SQL string?
So here's what I want to do on my MySQL database.
9 Answers
9
...
Performing Breadth First Search recursively
...vels, the results will be same as a BFS.
public void PrintLevelNodes(Tree root, int level) {
if (root != null) {
if (level == 0) {
Console.Write(root.Data);
return;
}
PrintLevelNodes(root.Left, level - 1);
PrintLevelNodes(root.Right, level...
How do I check CPU and Memory Usage in Java?
... }
public String DiskInfo() {
/* Get a list of all filesystem roots on this system */
File[] roots = File.listRoots();
StringBuilder sb = new StringBuilder();
/* For each filesystem root, print some info */
for (File root : roots) {
sb.append...
GROUP_CONCAT ORDER BY
...
@aleroot, Is this query MySQL specific?
– Pacerier
Apr 30 '15 at 20:24
...