This first query will return all of the tables in the database you are querying. To Show the TABLES and COLUMNS in the database or find TABLES and COLUMNS. We will be using a couple of the views in the information schema in order to run queries that help determine the makeup of tables in the data source. ![]() Information schema views enable applications to work correctly although significant changes have been made to the underlying system tables.” ![]() As their support documentation states, “Information schema views provide an internal, system table-independent view of the SQL Server metadata. Microsoft SQL Server provides an information schema view as one of several methods for obtaining this metadata. MySQL no database selected is an error that occurs when you execute a statement without first selecting a database. Querying the metadata on a data source is the easiest way to determine the makeup of a table if you don’t have an understanding of it already. This tutorial will help solve these problems. Understanding the schema and what tables are in it help to write efficient SQL and helps avoid running queries multiple times just to see if the schema name or column name is correct. This article demonstrates how to check the size of MySQL databases and tables by using the phpMyAdmin web interface or the command-line mysql program. The WHERE clause provides more flexibility to list the database that matches the given condition in the SQL statement.When writing queries for a database you might be new to, or one that changes often, you might want to run a quick check to find all the tables in a specific database, or the columns in the database, or to search if table or column exists. This command will show the same list of databases as the SHOW DATABASES. The LIKE clause list the database name that matches the specified pattern. In MySQL, you can use the SHOW SCHEMA command, as well, to list the databases. Let’s try to understand the SHOW DATABASES command with the help of these examples. The LIKE clause, if present on its own, indicates. SHOW SCHEMAS is a synonym for SHOW DATABASES. Show Databases command in MySQL also provides an option that allows us to filter the returned database using different pattern matching with LIKE and WHERE clause. SHOW DATABASES lists the databases on the MariaDB server host. MySQL: 'show databases command returning different results depending on how it is started. ![]() schemaname - database (schema) name Rows. Show statement (option 2) show schemas Columns. Show statement (option 1) show databases C. select schemaname as databasename from informationschema.schemata order by schemaname B. We can understand it with the following output: List Databases Using Pattern Matching The query below lists databases (schemas) on MySQL instance. This command is the synonyms of the SHOW DATABASES and gives the same result. MySQL also allows us another command to list the databases, which is a SHOW SCHEMAS statement. ![]() We can see the following output that explains it more clearly: Finally, run the SHOW Databases command to list/show databases. Now, you are connected to the MySQL server host, where you can execute all the SQL statements. Next, log in to the MySQL database server using the password that you have created during the installation of MySQL. Open the MySQL Command Line Client that appeared with a mysql> prompt.
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