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Django migration strategy for renaming a model and relationship fields
...different name, and the migration it creates will lose any data in the old table." Django 2.1 Docs For me, it was sufficient to create an empty migration, add the model renames to it, then run makemigrations as usual.
– hlongmore
Jan 15 '19 at 9:05
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What are the use cases for selecting CHAR over VARCHAR in SQL?
... Another reason is page splits and fragmentation. I had a table with an IDEN PK that got 99% fragmented because of page splits on varchar columns. A very active table and by nature of the application a new row empty row would get created and then populated. Char fixed the fragme...
How do you check if a certain index exists in a table?
....indexes
WHERE name='YourIndexName' AND object_id = OBJECT_ID('Schema.YourTableName')
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List of ANSI color escape sequences
... underlined (4) and the last part clears all this (0).
As described in the table below, there are a large number of text properties you can set, such as boldness, font, underlining, &c. (Isn't it silly that StackOverflow doesn't allow you to put proper tables in answers?)
Font Effects
╔══...
How to create a printable Twitter-Bootstrap page
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Bootstrap 3.2 update: (current release)
Current stable Bootstrap version is 3.2.0.
With version 3.2 visible-print deprecated, so you should use like this:
Class Browser Print
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.visible-print-block ...
What is your naming convention for stored procedures? [closed]
...hat if the sproc queries information from both the Customer and the Orders table?
– DOK
Oct 26 '08 at 18:27
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How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?
...aster-slave replication from scratch:
At the master:
RESET MASTER;
FLUSH TABLES WITH READ LOCK;
SHOW MASTER STATUS;
And copy the values of the result of the last command somewhere.
Without closing the connection to the client (because it would release the read lock) issue the command to get a d...
SQLite: How do I save the result of a query as a CSV file?
...ex = False)
You can customize the query to only export part of the sqlite table to the CSV file.
You can also run a single command to export all sqlite tables to CSV files:
for table in c.execute("SELECT name FROM sqlite_master WHERE type='table';").fetchall():
t = table[0]
df = pd.read_sql...
Changing column names of a data frame
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Try setnames() in the data.table package. Use something like setnames(DT,"b","B") or setnames(DT,c("a","E"),c("A","F"))
– dwstu
Aug 11 '14 at 17:23
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How to Implement Custom Table View Section Headers and Footers with Storyboard
...simply drag a UIView onto the canvas, lay it out and then set it in the tableView:viewForHeaderInSection or tableView:viewForFooterInSection delegate methods.
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