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Inner join vs Where
... for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FROM table1 t1
INNER JOIN table2 t2 ON t1.id = t2.id;
SELECT *
FROM TABLE (DBMS_XPLAN.DISPLAY);
-- 0 select statement
-- 1 hash join (access("T1"."ID"="T2"."ID"))
-- 2 table access full table1
-- 3 table access ful...
Iterating each character in a string using Python
...of which start with 0. So I need to find a "0" and grab it and the next 3 characters, and move on without duplicating the number if there's another 0 following it. None of the "for c in str" or "for i,c in enumerate(str)" methods work because I need control of the index. I'm sure a regular express...
Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
...
Avoiding if statement inside a for loop?
... f(index++, e);
}
int main() {
using namespace std;
set<char> s{'b', 'a', 'c'};
// indices starting at 1 instead of 0
for_each_indexed(s, [](size_t i, char e) { cout<<i<<'\t'<<e<<'\n'; }, 1u);
cout << "-----" << endl;
vecto...
In C# check that filename is *possibly* valid (not that it exists) [duplicate]
... You can add a check for your filename containing any of the characters in the array returned by char[] badChars = Path.GetInvalidFileNameChars();
– Jon Dosmann
Feb 12 '15 at 18:27
...
How to delete or add column in SQLITE?
... as long as you do a create new table first instead of a create from select, it will have all those things.
– John Lord
Jul 3 '19 at 15:28
1
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No identities were available - administrator request
...uble click) the new provisioning profile.
In your project's build settings select the NEW provisioning profile (it might have the same name as the old one)
In your project's build settings update your code signing identities (all of them) to the new one if there is one. (The old one was probably exp...
SQL Server: Is it possible to insert into two tables at the same time?
...LARE @DataID int;
INSERT INTO DataTable (Column1 ...) VALUES (....);
SELECT @DataID = scope_identity();
INSERT INTO LinkTable VALUES (@ObjectID, @DataID);
COMMIT
The good news is that the above code is also guaranteed to be atomic, and can be sent to the server from a client application w...
MySQL Select Date Equal to Today
I'm trying to run a mysql select statement where it looks at today's date and only returns results that signed up on that current day. I've currently tried the following, but it doesn't seem to work.
...
How do I get jQuery to select elements with a . (period) in their ID?
...wo backslashes before each special character.
A backslash in a jQuery selector escapes the next character. But you need
two of them because backslash is also the escape character for JavaScript
strings. The first backslash escapes the second one, giving you one actual
backslash in your st...