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PostgreSQL query to list all table names?
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What bout this query (based on the description from manual)?
SELECT table_name
FROM information_schema.tables
WHERE table_schema='public'
AND table_type='BASE TABLE';
share
|
im...
What is the worst real-world macros/pre-processor abuse you've ever come across?
...non-C++ programmer: Is the main problem here that a threadsafe function is converted into a non-threadsafe one? Or that InterlockedIncrement expects a pointer, so now you'll increase the pointer instead of what it's pointing at? Or both?
– Tim Pietzcker
Sep 20 ...
How to detect Ctrl+V, Ctrl+C using JavaScript?
... Dude! Thanks! This is exactly what I needed to enable users to select an "element" (calendar entry) in a web app I'm writing, hit ctrl + c to "copy" it, then ctrl+v to "paste" it, all without actually interacting with the allmighty blessed clipboard. ctrl+c I remember what they're clicke...
Determine the data types of a data frame's columns
...ric"
To change data type of a column:
library(hablar)
mtcars %>%
convert(chr(mpg, am),
int(carb))
converts columns mpg and am to character and the column carb to integer:
# A tibble: 32 x 11
mpg cyl disp hp drat wt qsec vs am gear carb
<chr> &l...
Maven error “Failure to transfer…”
...ed.properties).
Then go back into Eclipse, Right-click on the project and select Maven > Update Project. I selected to "Force Update of Snapshots/Releases". Click Ok and the dependencies finally resolved correctly.
shar...
Join between tables in two different databases?
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Yes, assuming the account has appropriate permissions you can use:
SELECT <...>
FROM A.table1 t1 JOIN B.table2 t2 ON t2.column2 = t1.column1;
You just need to prefix the table reference with the name of the database it resides in.
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Adding devices to team provisioning profile
...e.com
Add the UDID in devices
Go back to XCode, open up the Organizer and select "Provisioning Profiles", ensure that "Automatic Device Provisioning" is checked on the top right pane, then click on the "Refresh" button, and magically all your devices set in the provisioning portal will be automati...
How to add leading zeros?
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Note that sprintf converts numeric to string (character).
– aL3xa
Apr 28 '11 at 8:54
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Items in JSON object are out of order using “json.dumps”?
I'm using json.dumps to convert into json like
6 Answers
6
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Difference between a theta join, equijoin and natural join
...ed SQL query would be like this (you can play with all the examples here)
SELECT *
FROM Product
JOIN Component
ON Product.Pname = Component.Pname
and the result:
| PNAME | PRICE | CNAME | COST |
----------------------------------
| Laptop | 1500 | CPU | 500 |
| Laptop | 1500 | hdd ...