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Select rows which are not present in other table
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There are basically 4 techniques for this task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgr...
In Docker, what's the difference between a container and an image? [duplicate]
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@Faccion I get error: "Error response from daemon: Container 48cff2e9be75... is not running"
– geoidesic
Mar 22 '18 at 15:59
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Function to clear the console in R and RStudio
...ng function
clc <- function() cat(rep("\n", 50))
which you can then call as clc().
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add column to mysql table if it does not exist
...uld be to just try the ALTER TABLE ADD COLUMN command. It should throw an error if the column already exists.
ERROR 1060 (42S21): Duplicate column name 'newcolumnname'
Catch the error and disregard it in your upgrade script.
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How to Execute SQL Server Stored Procedure in SQL Developer?
... Are there any exceptions to this rule? I seem to be getting the error "Incorrect syntax near 'sp_dev_mystoredproc'." when executing with this syntax.
– nuzzolilo
Oct 24 '15 at 2:30
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Minimizing NExpectation for a custom distribution in Mathematica
...g from that guess
FindMinimum[MRL[start], {start, 0.05}]
and after some errors (your function is not defined below 0, so I guess the minimizer pokes a little in that forbidden region) we get
{0.0418137, {start -> 0.0584312}}
So the optimum should be at start = 0.0584312 with a mean residual ...
How to use the toString method in Java?
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object. In general, the toString
method returns a string that
"textually represents" this object.
The result should be a concise but
informative representation that is
easy for a person to read. It is
recommended that all subclasses
override this method.
The toString method fo...
Compare two DataFrames and output their differences side-by-side
...d code to take care of minor differences in datatype, which would throw an error, if you didn't account for it.
– Roobie Nuby
Mar 30 '18 at 4:45
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How to force Selenium WebDriver to click on element which is not currently visible?
...ny times I've had two elements at play and one is hidden and gives me this error.
– Chris
Jun 11 '19 at 15:53
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How does the const constructor actually work?
...r because the field 'j' is initialized with a non-constant value
Runtime Error:
/main.dart': error: line 5 pos 17: expression is not a valid compile-time constant
final int j = new DateTime.now().millisecond;
shar...