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Testing if object is of generic type in C#
... public void SimpleGenericInterfaces()
{
Assert.IsTrue(typeof(Table<string>).IsOfGenericType(typeof(IEnumerable<>)));
Assert.IsTrue(typeof(Table<string>).IsOfGenericType(typeof(IQueryable<>)));
Type concreteType;
Assert.IsTrue(typeof(Tabl...
What is the difference between UNION and UNION ALL?
...cted columns need to be of the same data type.
Example: If we have two tables, 1) Employee and 2) Customer
Employee table data:
Customer table data:
UNION Example (It removes all duplicate records):
UNION ALL Example (It just concatenate records, not eliminate duplicates, so it...
Making heatmap from pandas DataFrame
... and you're simply interested in adding color to represent the values in a table format, you can use the style.background_gradient() method of the pandas data frame. This method colorizes the HTML table that is displayed when viewing pandas data frames in e.g. the JupyterLab Notebook and the result ...
How do I bind Twitter Bootstrap tooltips to dynamically created elements?
...
great! for use inside a table add container: 'body' to avoid extra width.
– shock_gone_wild
Jan 19 '16 at 16:31
...
Where does PostgreSQL store the database?
...ory;
To see all the run-time parameters, use
show all;
You can create tablespaces to store database objects in other parts of the filesystem. To see tablespaces, which might not be in that data directory, use this query.
SELECT * FROM pg_tablespace;
...
How does Rails keep track of which migrations have run for a database?
...
Rails creates a table in your database called schema_migrations to keep track of which migrations have run.
The table contains a single column, version. When Rails runs a migration, it takes the leading digits in the migration's file name a...
Run a single migration file
...
Note that if you do this, it probably won't update the schema_migrations table, but it seems like that's what you want anyway.
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How to declare variable and use it in the same Oracle SQL script?
...or
DEFINE stupidvar = 'stupidvarcontent';
SELECT stupiddata
FROM stupidtable
WHERE stupidcolumn = '&stupidvar'
upd:
SQL*Plus: Release 10.2.0.1.0 - Production on Wed Aug 25 17:13:26 2010
Copyright (c) 1982, 2005, Oracle. All rights reserved.
SQL> conn od/od@etalon
Connected.
SQL>...
What MIME type should I use for CSV?
... Jun 27 '12 at 13:31
LittleBobbyTables - Au Revoir
29.5k1212 gold badges9393 silver badges110110 bronze badges
answered Aug 16 '11 at 9:24
...
Prevent row names to be written to file when using write.csv
..., "t.csv")
If you need to write big data out, use fwrite() from the data.table package. It's much faster than both write.csv and write_csv
# install.packages('data.table')
library(data.table)
fwrite(t, "t.csv")
Below is a benchmark that Edouard published on his site
microbenchmark(write.csv(d...