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SQL – Show Databases
Many a times you face a situation where you need to list down all the available databases. MySQL provides a convenient way to list down all the databases using SHOW DATABASES command where as there is no particular command in MS SQL Server to show or list the databases but, you can use the SELECT…FROM command as a work around list down available databases.
List Databases using SQL
The SQL SHOW DATABASES statement is used to list down all the available databases in MySQL database. You can use SHOW SCHEMAS as an alternate command for SHOW DATABASES.
Syntax
Following is the syntax of SQL SHOW DATABASES to list down all the available databases in MySQL −
SHOW DATABASES [LIKE ''pattern'' | WHERE expr] ;
We can use LIKE or WHERE clause along with SHOW DATABASES to filter out a list of databases.
Example
Following is an example to list down all the available databases.
SHOW DATABASES;
The output will be displayed as follows. This output depends on the number of databases available in the system −
| Database |
|---|
| performance_schema |
| information_schema |
| mysql |
| testDB |
Following is an example to list down all the databases whose name starts with test.
SHOW DATABASES LIKE ''test%
The output will be displayed as follows −
| Database (test%) |
|---|
| testDB |
The SHOW SCHEMAS Statement
You can use the SHOW SCHEMAS statement as an alternate for the SHOW DATABASES statement.
Syntax
Following is the syntax of the SQL SHOW SCHEMAS statement to list down all the available databases in MySQL −
SHOW SCHEMAS [LIKE ''pattern'' | WHERE expr] ;
We can use LIKE or WHERE clause along with SHOW SCHEMAS to filter out a list of databases.
Example
Following is an example to list down all the available databases.
SHOW SCHEMAS;
The output will be displayed as follows. This output depends on the number of databases available in the system −
| Database |
|---|
| performance_schema |
| information_schema |
| mysql |
| testDB |
Following is an example to list down all the databases whose name starts with test.
SHOW SCHEMAS LIKE ''test%
The output will be displayed as follows −
| Database (test%) |
|---|
| testDB |
The SELECT…FROM Statement
If you are working with MS SQL Server then you can use the SELECT…FROM statement to list down all the available databases as shown below.
SQL> SELECT * FROM sys.databases;
Output
If we execute the above query, it returns a table that lists down all the databases and associated information about the databases.
| name | database_id | source_database_id | owner_sid |
|---|---|---|---|
| master | 1 | NULL | 001 |
| tempdb | 2 | NULL | 001 |
| model | 3 | NULL | 001 |
| msdb | 4 | NULL | 001 |
| testDB | 5 | NULL | 001000 |
The EXEC sp_databases Statement
If you are using MS SQL Server then you can use the following EXEC sp_databases statement to list down all the databases −
SQL> EXEC sp_databases;
Output
This will display the same result as we got from SELECT…FROM statement.
| name | database_id | source_database_id | owner_sid |
|---|---|---|---|
| master | 1 | NULL | 001 |
| tempdb | 2 | NULL | 001 |
| model | 3 | NULL | 001 |
| msdb | 4 | NULL | 001 |
| testDB | 5 | NULL | 001000 |
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