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Postgresql - change the size of a varchar column to lower length
... really large table (almost 30 millions rows).
One of its columns is a varchar(255) and I would like to resize it to a varchar(40) .
Basically, I would like to change my column by running the following command:
...
Select last row in MySQL
How can I SELECT the last row in a MySQL table?
10 Answers
10
...
How to select from subquery using Laravel Query Builder?
... Note that if you have a complex query as a belongsToMany as subselect you have to add getQuery() twice => $sub->getQuery()->getQuery()
– Jordi Puigdellívol
Aug 28 '15 at 14:23
...
What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
...ent attribute. Otherwise, (valid at least for PG) you might get ERROR: for SELECT DISTINCT, ORDER BY expressions must appear in select list
– long
Apr 21 at 14:08
add a commen...
How to find all the tables in MySQL with specific column names in them?
... all tables with columns columnA or ColumnB in the database YourDatabase:
SELECT DISTINCT TABLE_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME IN ('columnA','ColumnB')
AND TABLE_SCHEMA='YourDatabase';
...
SQLite with encryption/password protection
...ing str)
{
byte[] bytes = new byte[str.Length * sizeof(char)];
bytes = System.Text.Encoding.Default.GetBytes(str);
return bytes;
}
}
}
Optionally, you can remove conn.SetPassword(passwordBytes);, and replace it with conn.ChangePassword("passw...
MySQL: How to copy rows, but change a few fields?
...able
( Event_ID
, col2
...
)
SELECT "155"
, col2
...
FROM Table WHERE Event_ID = "120"
Here, the col2, ... represent the remaining columns (the ones other than Event_ID) in your table.
...
HTML Form: Select-Option vs Datalist-Option
I was wondering what the differences are between Select-Option and Datalist-Option. Is there any situation in which it would be better to use one or the other? An example of each follows:
...
How do I specify new lines on Python, when writing on files?
...ly do the job. If you really want to get it right, you look up the newline character in the os package. (It's actually called linesep.)
Note: when writing to files using the Python API, do not use the os.linesep. Just use \n; Python automatically translates that to the proper newline character for ...
What do I need to do to get Internet Explorer 8 to accept a self signed certificate?
... certificate.”, choose “Continue to this website (not recommended).”
Select Tools➞Internet Options.
Select Security➞Trusted sites➞Sites.
Confirm the URL matches, and click “Add” then “Close”.
Close the “Internet Options” dialog box with either “OK” or “Cancel”.
Refres...
