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In MySQL queries, why use join instead of where?
...FROM clause
Write the association between the tables in the WHERE clause
SELECT *
FROM TABLE_A a,
TABLE_B b
WHERE a.id = b.id
Here's the query re-written using ANSI-92 JOIN syntax:
SELECT *
FROM TABLE_A a
JOIN TABLE_B b ON b.id = a.id
From a Performance Perspective:
Where su...
Where is SQL Server Management Studio 2012?
...all the entire SQL Server package, later on in the install process you can select to only install SSMS.
– Baodad
Jul 24 '13 at 18:21
...
How do I get a substring of a string in Python?
...is a step. So reversing a string is as simple as:
some_string[::-1]
Or selecting alternate characters would be:
"H-e-l-l-o- -W-o-r-l-d"[::2] # outputs "Hello World"
The ability to step forwards and backwards through the string maintains consistency with being able to array slice from the star...
Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column).
Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...
Faster s3 bucket duplication
...
If you don't mind using the AWS console, you can:
Select all of the files/folders in the first bucket
Click Actions > Copy
Create a new bucket and select it
Click Actions > Paste
It's still fairly slow, but you can leave it alone and let it do its thing.
...
A weighted version of random.choice
...dom.choice (each element in the list has a different probability for being selected). This is what I came up with:
25 Answ...
Writing data into CSV file in C#
...re the values
var allLines = (from trade in proposedTrades
select new object[]
{
trade.TradeType.ToString(),
trade.AccountReference,
trade.SecurityCodeType.ToString(),
trade.SecurityC...
Convert MySql DateTime stamp into JavaScript's Date format
...d.
A MySQL DATETIME column can be converted to a unix timestamp through:
SELECT unix_timestamp(my_datetime_column) as stamp ...
We can make a new JavaScript Date object by using the constructor that requires milliseconds since the epoch. The unix_timestamp function returns seconds since the epoc...
There is already an open DataReader associated with this Command which must be closed first
...s =
from account in context.Accounts
from guranteer in account.Gurantors
select new AccountsReport
{
CreditRegistryId = account.CreditRegistryId,
AccountNumber = account.AccountNo,
DateOpened = account.DateOpened,
};
return accounts.AsEnumerable()
.Select((account, ind...
mysql - how many columns is too many?
...every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name the columns you need.
As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entit...