Suppose you just want to change the name of a column, you could run an ALTER TABLE statement to do so.ĪLTER TABLE MyTable CHANGE COLUMN `Old Name` to `New Name` For example, to get the unique combination of city and state from a table, you can create the following view:ĬREATE VIEW distinct_cities_and_states AS In this case, MySQL relies on the combination of values in these columns to determine their uniqueness in the result set. The DISTINCT clause also works with more than one column. Rather than execute the above query every time that we wanted to see the distict employees we could create a view that we can execute queries against:Ģ: Retrieve Unique Data from Multiple Columns We can create a SELECT DISTINCT query that will do that: Suppose you have a database filled with thousands of employee records and youd like to know how many unique employee last names there are within the thousands of rows. 1: Retrieve Unique Values from a Single Column In today's blog, I'll be sharing a few tips and tricks for MySQL that you can apply using either Navicat for MySQL or Navicat Premium. Moreover, you can save your work to the Cloud for reuse and collaborating with team members. Both help you create views, queries and functions using an easy-to-use GUI interface. Navicat Premium is a database development tool that allows you to simultaneously connect to MySQL, MariaDB, MongoDB, SQL Server, Oracle, PostgreSQL, and SQLite databases from a single application, and is also compatible with cloud databases. In addition to MySQL and MariaDB, Navicat for MySQL also supports a number of cloud services, including Amazon RDS, Amazon Aurora, Oracle Cloud, Google Cloud, Microsoft Azure, Alibaba Cloud, Tencent Cloud and Huawei Cloud. If you work regularly with MySQL or MariaDB, then you will probably find Navicat Premium or Navicat for MySQL to be indispensable.
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