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Most efficient way to prepend a value to an array
...g an array to the front of another array, it is more efficient to just use concat. So:
var newArray = values.concat(oldArray);
But this will still be O(N) in the size of oldArray. Still, it is more efficient than manually iterating over oldArray. Also, depending on the details, it may help you, b...
Creating dataframe from a dictionary where entries have different lengths
...
You can also use pd.concat along axis=1 with a list of pd.Series objects:
import pandas as pd, numpy as np
d = {'A': np.array([1,2]), 'B': np.array([1,2,3,4])}
res = pd.concat([pd.Series(v, name=k) for k, v in d.items()], axis=1)
print(res)
...
How do I add more members to my ENUM-type column in MySQL?
... do not appear in your ENUM. What is the output of the following command?
SELECT DISTINCT country FROM carmake;
ANOTHER EDIT: What is the output of the following command?
SHOW VARIABLES LIKE 'sql_mode';
Is it STRICT_TRANS_TABLES or STRICT_ALL_TABLES? That could lead to an error, rather than the ...
How to remove element from array in forEach loop?
...se a string contains 'f', a result is different.
var review = ["of", "concat", "copyWithin", "entries", "every", "fill", "filter", "find", "findIndex", "flatMap", "flatten", "forEach", "includes", "indexOf", "join", "keys", "lastIndexOf", "map", "pop", "push", "reduce", "reduceRight", "reverse"...
How to get a list of MySQL views?
...to leave the "IN database_name" away if you look for view in the currently selected DB.
– kraftb
Jun 2 '15 at 17:11
To...
How to see full query from SHOW PROCESSLIST
... pull the data and look at 'INFO' column which contains the whole query :
select * from INFORMATION_SCHEMA.PROCESSLIST where db = 'somedb';
You can add any condition or ignore based on your requirement.
The output of the query is resulted as :
+-------+------+-----------------+--------+--------...
How to round an average to 2 decimal places in PostgreSQL?
... round that takes a precision is only available for numeric.
regress=> SELECT round( float8 '3.1415927', 2 );
ERROR: function round(double precision, integer) does not exist
regress=> \df *round*
List of functions
Schema | Name | Result data type | Argument...
How to get a list of user accounts using the command line in MySQL?
...
Use this query:
SELECT User FROM mysql.user;
Which will output a table like this:
+-------+
| User |
+-------+
| root |
+-------+
| user2 |
+-------+
As Matthew Scharley points out in the comments on this answer, you can group by the ...
How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
9
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How to add hyperlink in JLabel?
...rther escaping
private static String linkIfy(String s) {
return A_HREF.concat(s).concat(HREF_CLOSED).concat(s).concat(HREF_END);
}
//WARNING
//This method requires that s is a plain string that requires
//no further escaping
private static String htmlIfy(String s) {
return HTML.concat(s).co...