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Can I convert long to int?
...is the compiler default). It'll throw OverflowException in checked context if the value doesn't fit in an int:
int myIntValue = unchecked((int)myLongValue);
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MYSQL import data from csv using LOAD DATA INFILE
... just a note that the (col1, col2, col3....) is not required. Useful if you are creating a table on the fly before using this to insert data.
– Kieran Quinn
Mar 4 '19 at 14:16
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How to create relationships in MySQL
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If the tables are innodb you can create it like this:
CREATE TABLE accounts(
account_id INT NOT NULL AUTO_INCREMENT,
customer_id INT( 4 ) NOT NULL ,
account_type ENUM( 'savings', 'credit' ) NOT NULL,
balance...
Dump a mysql database to a plaintext (CSV) backup from the command line
...ysql to read. CSV seems more universal (one file per table is fine). But if there are advantages to mysqldump, I'm all ears. Also, I'd like something I can run from the command line (linux). If that's a mysql script, pointers to how to make such a thing would be helpful.
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Best way to iterate through a Perl array
...g. breadth-first searches): my @todo = $root; while (@todo) { my $node = shift; ...; push @todo, ...; ...; }
– ikegami
Feb 2 '15 at 14:40
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How to echo shell commands as they are executed
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If you also want to see which numbered line is being executed see stackoverflow.com/a/17805088/1729501
– user13107
Apr 19 '18 at 6:52
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What are Runtime.getRuntime().totalMemory() and freeMemory()?
...aximum amount of memory that the Java virtual machine will attempt to use. If there is no inherent limit then the value Long.MAX_VALUE will be returned.
freeMemory()
Returns the amount of free memory in the Java Virtual Machine. Calling the gc method may result in increasing the value returned by...
doGet and doPost in Servlets
...raw URL in browser address bar, etcetera will all fire a HTTP GET request. If a Servlet is listening on the URL in question, then its doGet() method will be called. It's usually used to preprocess a request. I.e. doing some business stuff before presenting the HTML output from a JSP, such as gatheri...
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
...om this answer which also contains a step-by-step MySQL+JDBC tutorial:
If you get a SQLException: Connection refused or Connection timed out or a MySQL specific CommunicationsException:
Communications link failure, then it means that the DB isn't reachable at all. This can have one or more of...
Function for Factorial in Python
...l (available in Python 2.6 and above):
import math
math.factorial(1000)
If you want/have to write it yourself, you can use an iterative approach:
def factorial(n):
fact = 1
for num in range(2, n + 1):
fact *= num
return fact
or a recursive approach:
def factorial(n):
i...