I Closed your post in SO, had been entertained.
1.read it first,
How number of columns affects performance?
2.When tables get too many columns,technically speaking, it's a design flaw.
Even limit is 4096,it's seldom to see a table columns>60.no engineer would like to design wide table.
It absolutely cause performance problem, and many unpredictable issues even crash. Cases I experienced such as backup database but it contain inconsistent data.
3.
when create those wide facts table, always "vertical split" wide table to several thin tables with the same primary key-id.
Normally revise 3 places:
Code:
// table_1 include column1-100, table_2 include column101-200
for($i=0; $i<=100; $i++) {
CREATE table_n(column1,column2,…column100
//switch tables or get _n from another individual table
switch ($column_n)
{
case $column_n > 100 && $column_n <= 200:
$table_n = 'table_1';
break;
case $column_n > 200 && $column_n <= 300 :
$table_n = 'table_2';
...
//join query If you select *
select * from table_1 inner join table_2
Try it, 30mins code work.
Btw, users reminder is always been appreciated.
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