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How to add a primary key to a MySQL table?
...le as it is written now, which can be a little confusing when doing simple SELECT * ...
– StefanK
Apr 12 '19 at 6:45
H...
Remove columns from dataframe where ALL values are NA
...
dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
...
MySQL Multiple Joins in one query?
...
You can simply add another join like this:
SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_message_id = dashboard_messages.id
INNER JO...
Is there an SQLite equivalent to MySQL's DESCRIBE [table]?
...aster table:
sqlite> CREATE TABLE foo (bar INT, quux TEXT);
sqlite> SELECT * FROM sqlite_master;
table|foo|foo|2|CREATE TABLE foo (bar INT, quux TEXT)
sqlite> SELECT sql FROM sqlite_master WHERE name = 'foo';
CREATE TABLE foo (bar INT, quux TEXT)
...
how to display full stored procedure code?
...
SELECT prosrc FROM pg_proc WHERE proname = 'function_name';
This tells the function handler how to invoke the function. It might be the actual source code of the function for interpreted languages, a link symbol, a file nam...
How to take backup of a single table in a MySQL database?
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You can use easily to dump selected tables using MYSQLWorkbench tool ,individually or group of tables at one dump then import it as follow: also u can add host information if u are running it in your local by adding -h IP.ADDRESS.NUMBER after-u usernam...
Grant execute permission for a user on all stored procedures in database?
...out having to call grant execute on the new stored procedure:
IF EXISTS (SELECT * FROM sys.database_principals WHERE name = N'asp_net')
DROP USER asp_net
GO
IF EXISTS (SELECT * FROM sys.database_principals
WHERE name = N'db_execproc' AND type = 'R')
DROP ROLE [db_execproc]
GO
--Create a databa...
Change One Cell's Data in mysql
...
I was confused by this answer, thinking SET selected rows to change, and WHERE changed them.
– Keith
May 30 '17 at 18:50
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Can “list_display” in a Django ModelAdmin display attributes of ForeignKey fields?
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@marcelm that’s what select_related is for. the get_queryset() of the UserAdmin will have to be overwritten.
– interDist
Jul 17 '17 at 21:38
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Is there a way to recover from an accidental “svn revert”?
...ou will find local history option, where you will find all the history for selected file, including all the operation you did with that file (update,commit, revert ).
Good luck,
Arkde
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