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Cannot simply use PostgreSQL table name (“relation does not exist”)
... is defined with a mixed-case spelling, and you're trying to query it with all lower-case.
In other words, the following fails:
CREATE TABLE "SF_Bands" ( ... );
SELECT * FROM sf_bands; -- ERROR!
Use double-quotes to delimit identifiers so you can use the specific mixed-case spelling as the tab...
How do I create test and train samples from one dataframe with pandas?
...
In the newest SciKit version you need to call it now as: from sklearn.cross_validation import train_test_split
– horseshoe
Mar 22 '17 at 9:32
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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...
Which icon sizes should my Windows application's icon include?
... 24, 32, 40, 48, 64, 96, 128 and 256. Then I checked which image is shown. All these were done with normal 96dpi. If using a larger DPI, the larger sizes may be used (only checked this a bit in Windows 7). The results:
Windows XP:
Explorer views:
Details / List: 16
Icons: 32
Tiles / Thumbnails: 48...
What is the optimal algorithm for the game 2048?
...empty position with a value of either 2 or 4 . The game terminates when all the boxes are filled and there are no moves that can merge tiles, or you create a tile with a value of 2048 .
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How to remove/delete a large file from commit history in Git repository?
I accidentally dropped a DVD-rip into a website project, then carelessly git commit -a -m ... , and, zap, the repo was bloated by 2.2 gigs. Next time I made some edits, deleted the video file, and committed everything, but the compressed file is still there in the repository, in history.
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`testl` eax against eax?
...s popular answer into a better canonical answer to "what's this TEST thing all about, and how is it different from CMP", which is sort of implied. See my own answer further down for comments about the semantic meaning of the synonymous JE and JZ. Please review my edit since it's pretty major, and ...
How do I get SUM function in MySQL to return '0' if no values are found?
...iddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nulls, and one with a mixture):
SQL Fiddle
MySQL 5.5.32 Schema Setup:
CREATE TABLE foo
(
id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
val INT
);
INSERT INTO foo (val) VALUES
(null),(1),(n...
Internet Explorer 9 not rendering table cells properly
...umns outside the boundries of my table.
I fixed this by doing something really silly; removing all the spaces betwen the <td> start and end tags and left justifying the HTML markup pertaining to my table. Basically, you want all of your <td> </td> on the same line, no spaces.
Exa...
Where is Java's Array indexOf?
I must be missing something very obvious, but I've searched all over and can't find this method.
13 Answers
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