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Is there a python equivalent of Ruby's 'rvm'?
...
Optionally, if you're using Macports you can use python_select.
Install python_select with:
$ sudo port install python_select
Assuming python 2.6 and 2.5 have bee installed via Macports you can switch pythons like so:
$ sudo python_select python25
=> Selecting version "pyth...
MongoDB SELECT COUNT GROUP BY
I am playing around with MongoDB trying to figure out how to do a simple
7 Answers
7
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How do I rename a column in a SQLite database table?
...lite.org/images/syntax/alter-table-stmt.gif
Example:
CREATE TABLE tab AS SELECT 1 AS c;
SELECT * FROM tab;
ALTER TABLE tab RENAME COLUMN c to c_new;
SELECT * FROM tab;
db-fiddle.com demo
Android Support
As of writing, Android's API 27 is using SQLite package version 3.19.
Based on the cu...
SQLite UPSERT / UPDATE OR INSERT
... at this code:
INSERT INTO players (id, name, age)
VALUES (
coalesce((select id from players where user_name='steven'),
(select max(id) from drawings) + 1),
32)
The trick is in coalesce. It returns the id of the user 'steven' if any, and otherwise, it returns a new fresh id.
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Accessing an SQLite Database in Swift
...pared statement: \(errmsg)")
}
statement = nil
Prepare new statement for selecting values from table and loop through retrieving the values:
if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
pri...
Error during installing HAXM, VT-X not working
...this, restart the computer, when the computer started then press Esc, then select the F2 if the manufacturer is dell.
Even if you have enabled the Virtualization (VT) in BIOS settings, some antivirus options prevent HAXM installation.
For example: In Avast antivirus under Settings (parameters) tab ...
In PHP with PDO, how to check the final SQL parametrized query? [duplicate]
..... and finally EXECUTE ....
You won't be able to get some SQL string like SELECT * FROM ..., even if it would produce equivalent results, because no such query was ever actually sent to the database.
share
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What is time_t ultimately a typedef to?
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[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 through:
# 131 "/usr/include/bits/types.h" 3 4
# 1 "/usr/inclu...
Effect of a Bitwise Operator on a Boolean in Java
...variables and operate on them bit by bit. In the case of integers, longs, chars this makes sense. These variables can contain the full range of values enforced by their size.
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The object 'DF__*' is dependent on column '*' - Changing int to double
...te void DropConstraint()
{
Sql(@"DECLARE @var0 nvarchar(128)
SELECT @var0 = name
FROM sys.default_constraints
WHERE parent_object_id = object_id(N'dbo.MyTable')
AND col_name(parent_object_id, parent_column_id) = 'Rating';
IF @var0 IS NOT NULL
...