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How to Store Historical Data
...y to store historical data. Currently, for some systems, I use a separate table to store historical data, and I keep an original table for the current, active record. So, let's say I have table FOO. Under my system, all active records will go in FOO, and all historical records will go in FOO_Hist...
INSERT statement conflicted with the FOREIGN KEY constraint - SQL Server
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In your table dbo.Sup_Item_Cat, it has a foreign key reference to another table. The way a FK works is it cannot have a value in that column that is not also in the primary key column of the referenced table.
If you have SQL Server ...
What are the uses for Cross Join?
...t
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might cross three tables:
select
hour,
minute
from
hours CROSS JOIN minute...
Table Header Views in StoryBoards
Is there a way to insert a Table Header View (tableHeaderView) in StoryBoard (like we used to do in Interface Builder)?
3 A...
How to have an automatic timestamp in SQLite?
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Just declare a default value for a field:
CREATE TABLE MyTable(
ID INTEGER PRIMARY KEY,
Name TEXT,
Other STUFF,
Timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
);
However, if your INSERT command explicitly sets this field to NULL, it will be set to NULL.
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Swapping column values in MySQL
I have a MySQL table with coordinates, the column names are X and Y. Now I want to swap the column values in this table, so that X becomes Y and Y becomes X. The most apparent solution would be renaming the columns, but I don't want to make structure changes since I don't necessarily have permission...
mysqldump data only
...for the syntax for dumping all data in my mysql database. I don't want any table information.
8 Answers
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How to deal with SQL column names that look like SQL keywords?
...ause I didn't make it.
Am I allowed to do something like SELECT from FROM TableName or is there a special syntax to avoid the SQL Server being confused?
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Long press on UITableView
I would like to handle a long press on a UITableViewCell to print a "quick access menu".
Did someone already do this?
10...
Pretty Printing a pandas dataframe
How can I print a pandas dataframe as a nice text-based table, like the following?
9 Answers
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