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How to use GROUP_CONCAT in a CONCAT in MySQL
If I have a table with the following data in MySQL:
7 Answers
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Access Denied for User 'root'@'localhost' (using password: YES) - No Privileges?
...ot password, we'll going to forcefully INSERT a record into the mysql.user table
In the init file, use this instead
INSERT INTO mysql.user (Host, User, Password) VALUES ('%', 'root', password('YOURPASSWORD'));
GRANT ALL ON *.* TO 'root'@'%' WITH GRANT OPTION;
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Order a MySQL table by two columns
How do I sort a MySQL table by two columns?
5 Answers
5
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Does Foreign Key improve query performance?
Suppose I have 2 tables, Products and ProductCategories. Both tables have relationship on CategoryId. And this is the query.
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Is an index needed for a primary key in SQLite?
When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all t...
Delete duplicate rows from small table
I have a table in a PostgreSQL 8.3.8 database, which has no keys/constraints on it, and has multiple rows with exactly the same values.
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Specify custom Date format for colClasses argument in read.table/read.csv
... way to specify the Date format when using the colClasses argument in read.table/read.csv?
4 Answers
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jQuery: count number of rows in a table
How do I count the number of tr elements within a table using jQuery?
11 Answers
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How to do an INNER JOIN on multiple columns
...nds flights either by the city name or the airport code, but the flights table only contains the airport codes so if I want to search by city I have to join on the airports table.
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What's the difference between using INDEX vs KEY in MySQL?
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There's no difference. They are synonyms.
From the CREATE TABLE manual entry:
KEY is normally a synonym for INDEX. The key attribute PRIMARY KEY can
also be specified as just KEY when given in a column definition. This was
implemented for compatibility with other database sy...