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PostgreSQL: insert from another table
I'm trying to insert data to a table from another table and the tables have only one column in common. The problem is, that the TABLE1 has columns that won't accept null values so I can't leave them empty and I can't get them from the TABLE2.
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Find integer index of rows with NaN in pandas dataframe
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And just in case, if you want to find the coordinates of 'nan' for all the columns instead (supposing they are all numericals), here you go:
df = pd.DataFrame([[0,1,3,4,np.nan,2],[3,5,6,np.nan,3,3]])
df
0 1 2 3 4 5
0 0 1 3 4.0 NaN 2
1 3 5 6 NaN 3.0 3
np.where(np.as...
How do I center align horizontal menu?
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From http://pmob.co.uk/pob/centred-float.htm:
The premise is simple and basically just involves a widthless float wrapper that is floated to the left and then shifted off screen to the left width position:relative; left:-50%. Next the nested inner element is reversed and a relative position o...
Why doesn't Haskell's Prelude.read return a Maybe?
...ersions floating around many codebases).
See also this discussion.
Personally, I use the version from the safe package.
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How to access the correct `this` inside a callback?
...d inside each function and its value only depends on how the function was called, not how/when/where it was defined. It is not affected by lexical scopes like other variables (except for arrow functions, see below). Here are some examples:
function foo() {
console.log(this);
}
// normal functio...
python's re: return True if string contains regex pattern
...p.search(word) <_sre.SRE_Match object at 0x101030b28> . You can drop all the pipe symbols.
– radtek
Jan 27 '17 at 14:51
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Reverse / invert a dictionary mapping
...g aspect of this new implementation is considered an implementation detail and should not be relied upon. There is no guarantee it will stay that way so don't write code relying on Dict having the same behavior as OrderedDict.
– Mattias
Aug 26 '18 at 17:44
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Java SE 6 vs. JRE 1.6 vs. JDK 1.6 - What do these mean?
I see many different Java terms floating around. I need to install the JDK 1.6. It was my understanding that Java 6 == Java 1.6. However, when I install Java SE 6, I get a JVM that reports as version 11.0! Who can solve the madness?
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Build tree array from flat array in javascript
I have a complex json file that I have to handle with javascript to make it hierarchical, in order to later build a tree.
Every entry of the json has :
id : a unique id,
parentId : the id of the parent node (which is 0 if the node is a root of the tree)
level : the level of depth in the tree
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What is the best django model field to use to represent a US dollar amount?
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I think this example is correct almost to all currencies. To represent currencies as Bitcoin, I think is much better to use an integer field to save the amount in satoshis, and then show it to the final user in the representation that you want (BTC, mBTC, etc)
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