First check if it’s a workbench or connection problem. 1) In your windows run ‘cmd’ to open a terminal Try both 2a) mysql -u root -p -h 127.0.0.1 -P 3306 2b) mysql -u root -p -h > localhost -P 3306 3) If the connection is good you will get a password prompt, see if you can connect … Read more
A source of confusion may be the use of the word in two different contexts – data modelling and database query optimization. In data modelling terms, cardinality is how one table relates to another. 1-1 (one row in table A relates to one row in tableB) 1-Many (one row in table A relates to many … Read more
Amazingly, “relation” in “relational” databases does not refer to the foreign key relationship of one table to another. “A relation is a data structure which consists of a heading and an unordered set of tuples which share the same type,” according to Wikipedia on ‘Relation (database)’. In SQL RDBMSes (such as MS SQL Server and Oracle] tables are … Read more
Quote by @DAC In short: SID = the unique name of your DB, ServiceName = the alias used when connecting Not strictly true. SID = unique name of the INSTANCE (eg the oracle process running on the machine). Oracle considers the “Database” to be the files. Service Name = alias to an INSTANCE (or many … Read more
There is a lot of confusion around this, I will try to make it as simple as possible. The primary key is a general concept to indicate one or more columns used to retrieve data from a Table. The primary key may be SIMPLE and even declared inline: That means that it is made by a single … Read more
If the charset of the tables is the same as it’s content try to use mysql_set_charset(‘UTF8’, $link_identifier). Note that MySQL uses UTF8 to specify the UTF-8 encoding instead of UTF-8 which is more common. Check my other answer on a similar question too.
Restrictions You can ask the system catalog pg_database – accessible from any database in the same database cluster. The tricky part is that CREATE DATABASE can only be executed as a single statement. The manual: CREATE DATABASE cannot be executed inside a transaction block. So it cannot be run directly inside a function or DO … Read more
I just discovered csvkit, which is a set of Unix command-line tools for CSV files. I installed it on my Mac with pip install csvkit. The command was: You can alternatively provide a DB connection string and it can load the table directly.
This is commonly reported as an error due to using the wrong version of SSMS(Sql Server Management Studio). Use the version designed for your database version. You can use the command select @@version to check which version of sql server you are actually using. This version is reported in a way that is easier to … Read more
Every SQL database uses its own implementation of the language that varies slightly. While basic queries are almost universal, there are notable nuances between MySQL, PostgreSQL, Microsoft SQL Server, Oracle Database, etc. What’s particularly notable about SQLite is that unlike all the others mentioned above, this database software doesn’t come with a daemon that queries … Read more