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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...
Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'?,./
...al letters represent the negation of their lowercase counterparts.
\W will select all non "word" characters equivalent to [^a-zA-Z0-9_]
\S will select all non "whitespace" characters equivalent to [ \t\n\r\f\v]
_ will select "_" because we negate it when using the \W and need to add it back in
...
Create an array or List of all dates between two dates [duplicate]
...
LINQ:
Enumerable.Range(0, 1 + end.Subtract(start).Days)
.Select(offset => start.AddDays(offset))
.ToArray();
For loop:
var dates = new List<DateTime>();
for (var dt = start; dt <= end; dt = dt.AddDays(1))
{
dates.Add(dt);
}
EDIT:
As for padding value...
The superclass “javax.servlet.http.HttpServlet” was not found on the Java Build Path [duplicate]
...
Add a runtime first and select project properties. Then check the server name from the 'Runtimes' tab as shown in the image.
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How to create a jQuery plugin with methods?
... this technique! It doesn't create a new instance for every element in the selector like you think you're doing, instead it creates only a single instance attached to the selector itself. View my answer for a solution.
– Kevin Jurkowski
Apr 10 '14 at 1:14
...
MySQL OPTIMIZE all tables?
...>.<your_table>;, optimize all tables in a given schema like this: select concat('OPTIMIZE NO_WRITE_TO_BINLOG TABLE ',table_schema,'.',table_name,';') into outfile '/tmp/optimize_all_tables.sql' from information_schema.tables where table_schema = 'pabeta' and table_type = 'base table'; sourc...
Styling an input type=“file” button
...gt;
In terms of styling, just hide1 the input element using the attribute selector.
input[type="file"] {
display: none;
}
Then all you need to do is style the custom label element. (example).
.custom-file-upload {
border: 1px solid #ccc;
display: inline-block;
padding: 6px 12px;
...
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...
Find index of a value in an array
... return -1;
}
And you can use LINQ as well:
int keyIndex = words
.Select((v, i) => new {Word = v, Index = i})
.FirstOrDefault(x => x.Word.IsKey)?.Index ?? -1;
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MIN/MAX vs ORDER BY and LIMIT
...oks like MIN() is able to simply pluck the smallest value from the index ('Select tables optimized away' and 'NULL' rows) whereas the SORT and LIMIT still needs needs to do an ordered traversal of the index (106,000 rows). The actual performance impact is probably negligible.
It looks like MIN() i...