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Adding a regression line on a ggplot
...n <- function (fit) {
`require(ggplot2)
ggplot(fit$model, aes_string(x = names(fit$model)[2], y = names(fit$model)[1])) +
geom_point() +
stat_smooth(method = "lm", col = "red") +
labs(title = paste("Adj R2 = ",signif(summary(fit)$adj.r.squared, 5),
...
How to set initial value and auto increment in MySQL?
How do I set the initial value for an "id" column in a MySQL table that start from 1001?
10 Answers
...
How do I write JSON data to a file?
...on.dump writes to a file or file-like object, whereas json.dumps returns a string.
– phihag
Aug 13 '15 at 20:58
27
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Difference between left join and right join in SQL Server [duplicate]
...ed completely interchangeable. Try however Table2 left join Table1 (or its identical pair, Table1 right join Table2) to see a difference. This query should give you more rows, since Table2 contains a row with an id which is not present in Table1.
...
Difference between initLoader and restartLoader in LoaderManager
...s much more enlightening.
initLoader
Call to initialize a particular ID with a Loader. If this ID already
has a Loader associated with it, it is left unchanged and any previous
callbacks replaced with the newly provided ones. If there is not
currently a Loader for the ID, a new one is ...
How do I save a stream to a file in C#?
...
public void CopyStream(Stream stream, string destPath)
{
using (var fileStream = new FileStream(destPath, FileMode.Create, FileAccess.Write))
{
stream.CopyTo(fileStream);
}
}
s...
What's the difference between UTF-8 and UTF-8 without BOM?
...re is no official difference between UTF-8 and BOM-ed UTF-8
A BOM-ed UTF-8 string will start with the three following bytes. EF BB BF
Those bytes, if present, must be ignored when extracting the string from the file/stream.
But, as additional information to this, the BOM for UTF-8 could be a good ...
PostgreSQL Autoincrement
...
Yes, SERIAL is the equivalent function.
CREATE TABLE foo (
id SERIAL,
bar varchar);
INSERT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter SERIAL...
SQL Joins Vs SQL Subqueries (Performance)?
...vary. The speed will depend a lot on indexes (do you have indexes on both ID columns? That will help a lot...) among other things.
The only REAL way to tell with 100% certainty which is faster is to turn on performance tracking (IO Statistics is especially useful) and run them both. Make sure to...
Inserting data into a temporary table
...
INSERT INTO #TempTable (ID, Date, Name)
SELECT id, date, name
FROM physical_table
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