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How to define “type disjunction” (union types)?
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Miles Sabin describes a very nice way to get union type in his recent blog post Unboxed union types in Scala via the Curry-Howard isomorphism:
He first defines negation of types as
type ¬[A] = A => Nothing
using De Morgan's law this allows him to define union ty...
SQLAlchemy - Getting a list of tables
...aData.reflect() method. And notice, use engine = sqlalchemy.create_engine('mysql://user:password@host/db_name') rather than "mysql://user:password@host" and engine.execute("use db_name").
– Java Xu
Mar 21 '13 at 3:54
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Retrieve column names from java.sql.ResultSet
...equired libraries
import java.util.*;
import java.sql.*;
public class MySQLExample {
public void run(String sql) {
// JDBC driver name and database URL
String JDBC_DRIVER = "com.mysql.jdbc.Driver";
String DB_URL = "jdbc:mysql://localhost/demo";
// Database credentials
Str...
Difference between EXISTS and IN in SQL?
... t1Id INT, someData VARCHAR(20))
GO
INSERT INTO t1
SELECT 1, 'title 1', 5 UNION ALL
SELECT 2, 'title 2', 5 UNION ALL
SELECT 3, 'title 3', 5 UNION ALL
SELECT 4, 'title 4', 5 UNION ALL
SELECT null, 'title 5', 5 UNION ALL
SELECT null, 'title 6', 5
INSERT INTO t2
SELECT 1, 1, 'data 1' UNION ALL
SELECT...
PHP MySQL Google Chart JSON - Complete Example
... searched a lot to find a good example for generating a Google Chart using MySQL table data as the data source. I searched for a couple of days and realised that there are few examples available for generating a Google Chart (pie, bar, column, table) using a combination of PHP and MySQL. I finally m...
How to fix: “No suitable driver found for jdbc:mysql://localhost/dbname” error when using pools? [du
...c/1.3/drizzle-jdbc-1.3.jar && wget http://central.maven.org/maven2/mysql/mysql-connector-java/5.1.27/mysql-connector-java-5.1.27.jar
– jmojico
Dec 17 '19 at 16:38
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How to run an EXE file in PowerShell with parameters with spaces and quotes
...hod 1
A simple example
Start-Process -NoNewWindow -FilePath "C:\wamp64\bin\mysql\mysql5.7.19\bin\mysql" -ArgumentList "-u root","-proot","-h localhost"
In your case
Start-Process -NoNewWindow -FilePath "C:\Program Files\IIS\Microsoft Web Deploy\msdeploy.exe" -ArgumentList "-verb:sync","-source:dbfu...
Combine two ActiveRecord::Relation objects
...name_relation.merge(last_name_relation)
If you want to combine using OR (union), use or†:
first_name_relation.or(last_name_relation)
† Only in ActiveRecord 5+; for 4.2 install the where-or backport.
share
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MYSQL import data from csv using LOAD DATA INFILE
I am importing some data of 20000 rows from a CSV file into Mysql.
11 Answers
11
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What are Aggregates and PODs and how/why are they special?
...lass can also be an aggregate if… wait! nothing is said about structs or unions, can't they be aggregates? Yes, they can. In C++, the term class refers to all classes, structs, and unions. So, a class (or struct, or union) is an aggregate if and only if it satisfies the criteria from the above def...