| employee_id | first_name | last_name | email | phone_number | hire_date | job_id | salary | manager_id | department_id | It’s like a spreadsheet that contains rows and columns with a heading: +-+-+-+-+-+-+-+-+-+-+ The following shows the result sets returned by the database server. The following example uses the SQL SELECT statement to get data from all the rows and columns in the employees table: SELECT * FROM employees Code language: SQL (Structured Query Language) ( sql ) 1) SQL SELECT – selecting data from all columns example We’ll use the employees table in the sample database for demonstration purposes. This convention makes the SQL statements more readable. Therefore, the SELECT and select keywords have the same meaning.īy convention, we will use the uppercase letters for the SQL keywords, such as SELECT and FROM and the lowercase letters for the identifiers such as table and column names. If you want to query data from all the columns of the table, you can use the asterisk (*) operator instead if specifying all the column names: SELECT * FROM table_name Check out the SQL syntax for more information. The database server uses it to separate two SQL statements.įor example, if you execute two SQL SELECT statements, you need to separate them using the semicolon ( ). The semicolon ( ) is not part of a query. It’s like from a table, select data from these columns. When evaluating the SELECT statement, the database system evaluates the FROM clause first and then the SELECT clause. Then, specify the table name in the FROM clause.First, specify a list of comma-separated columns from the table in the SELECT clause.Table_name Code language: SQL (Structured Query Language) ( sql ) The following shows the basic syntax of the SELECT statement that selects data from a single table. The SQL SELECT statement selects data from one or more tables. Summary: in this tutorial, you will learn how to use the SQL SELECT statement to query data from a single table.
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