MYSQL05: Retrieving data using SELECT

Once the tables are populated with data, we can  ask for the data from the table. To retrieve the data from table, SELECT command is issued.

SELECT (field1, field2 ...) FROM tableName;

for example, to get id, name and age from the students table, the SELECT statement is written like this:

SELECT (id, name, age) FROM students;

this will return all the data with every fields from the students table. Another most common way is using asterisk symbol.

SELECT * FROM students;

 both the SQL statement above will return following result. (table with dash lines to distinguish the table in database and table you get in your program)

Id
name
age
1
Calvin
12
2
Joe
15
3
Rosy
17

We can also retrieve only certain field from the table. For example, to retrieve only the name from the entire table

SELECT (name) FROM students;

this will gives us:

name
Calvin
Joe
Rosy

although it is possible to get the entire table into out program and then process them by our self, we make use of all the capability provided by database server to help lessen the programming.

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