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Multiple INSERT statements vs. single INSERT with multiple VALUES
...ng the number of VALUES clauses and recording the compile time.
I then divided the compile time by the number of rows to get the average compile time per clause. The results are below
Up until 250 VALUES clauses present the compile time / number of clauses has a slight upward trend but nothing t...
What is the difference between “INNER JOIN” and “OUTER JOIN”?
...ally show any distinction between different types of join predicate or provide a framework for reasoning about how they will operate.
There is no substitute for understanding the logical processing and it is relatively straightforward to grasp anyway.
Imagine a cross join.
Evaluate the on clause ag...
Java - JPA - @Version annotation
...operty:
@Entity
public class MyEntity implements Serializable {
@Id
@GeneratedValue
private Long id;
private String name;
@Version
private Long version;
//...
}
On update, the field annotated with @Version will be incremented and added to the WHERE clause, some...
I am getting Failed to load resource: net::ERR_BLOCKED_BY_CLIENT with Google chrome
...
My advice is to avoid any image names; class names or ID's with the words:
Advert
Advertise
in their name!
I ran some tests and Ad blockers regularly block any direct content with these names either within the CSS file, Div or Span Layers...
Authenticate Jenkins CI for Github private repository
...ally fetch data from my private repository hosted on Github.
But I have no idea how to accomplish that task.. Tried the documentation, generating ssh-key for jenkins user and all what I can see is: "unable to clone the repo". I've checked URLs - they are valid.
...
Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
...
@colin, Not fully automatic, but you can use naresid to put the missing values back in after using na.exclude. A quick example: tmp <- data.frame(x=factor(c('a','b','c',NA,'a'))); tmp2 <- na.exclude(tmp); tmp3 <- model.matrix( ~x-1, tmp2); tmp4 <- naresid(attr(t...
Remove rows with all or some NAs (missing values) in data.frame
...
tidyr has a new function drop_na:
library(tidyr)
df %>% drop_na()
# gene hsap mmul mmus rnor cfam
# 2 ENSG00000199674 0 2 2 2 2
# 6 ENSG00000221312 0 1 2 3 2
df %>% drop_na(rn...
Remove last item from array
...n.js"></script>
<b>Original Array : </b>
<div id="div1"></div>
<br/>
<b>After slice(0, -1): </b>
<div id="div2"></div>
instead of doing :
arr.slice(-1); // returns [2]
Here is a demo:
var arr = [1, 0, 2];
var ne...
Elegant setup of Python logging in Django
... - the corresponding value will be a dict in which each key is a formatter id and each value is a dict describing how to configure the corresponding Formatter instance.
filters - the corresponding value will be a dict in which each key is a filter id and each value is a dict describing how to config...
Paging with Oracle
... a.*, rownum r__
FROM
(
SELECT * FROM ORDERS WHERE CustomerID LIKE 'A%'
ORDER BY OrderDate DESC, ShippingDate DESC
) a
WHERE rownum < ((pageNumber * pageSize) + 1 )
)
WHERE r__ >= (((pageNumber-1) * pageSize) + 1)
...