SQL > SQL Commands > Select

The SELECT statement in SQL is used to retrieve data from a relational database.

Syntax

Number of ColumnsSQL Syntax
1SELECT "column_name" FROM "table_name";
More Than 1SELECT "column_name1"[, "column_name2"] FROM "table_name";
AllSELECT * FROM "table_name";

"table_name" is the name of the table where data is stored, and "column_name" is the name of the column containing the data to be retrieved.

To select more than one column, add a comma to the name of the previous column, and then add the column name. If you are selecting three columns, the syntax will be,

SELECT "column_name1", "column_name2", "column_name3" FROM "table_name";

Note there is no comma after the last column selected.

Examples

We will provide examples for each of the following three use cases:

Let's use the following table to illustrate all three cases:

Table Store_Information

Store_NameSalesTxn_Date
Los Angeles1500Jan-05-1999
San Diego250Jan-07-1999
Los Angeles300Jan-08-1999
Boston700Jan-08-1999

Example 1: Select one column

To select a single column, we specify the column name between SELECT and FROM as follows:

SELECT Store_Name FROM Store_Information;

Result:

Store_Name
Los Angeles
San Diego
Los Angeles
Boston

Example 2: Select multiple columns

We can use the SELECT statement to retrieve more than one column. To select Store_Name and Sales columns from Store_Information, we use the following SQL:

SELECT Store_Name, Sales FROM Store_Information;

Result:

Store_NameSales
Los Angeles1500
San Diego250
Los Angeles300
Boston700

Example 3: Select all columns

There are two ways to select all columns from a table. The first is to list the column name of each column. The second, and the easier, way is to use the symbol *. For example, to select all columns from Store_Information, we issue the following SQL:

SELECT * FROM Store_Information;

Result:

Store_NameSalesTxn_Date
Los Angeles1500Jan-05-1999
San Diego250Jan-07-1999
Los Angeles300Jan-08-1999
Boston700Jan-08-1999

Exercises

For these exercises, assume we have a table called Users with the following columns:

Table Users

Column Name
First_Name
Last_Name
Birth_Date
Gender
Date_Joined

1. Which of the following SQL statement is incorrect? (There can be more than one answer)
a) SELECT * FROM Users;
b) SELECT First_Name, Gender, Last_Name FROM Users;
c) SELECT First_Name, Last_Name Users;
d) SELECT All FROM Users;

2. (True Or False) In SQL, the order of the columns in a SELECT statement must be the same as the order of the columns in the underlying table. For example, in the table Users, you must select First_Name before Last_Name.

3. (True Or False) The following two SQL statements are equivalent:
a) Select * From Users;
b) SELECT * FROM Users;

Next: SQL DISTINCT




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