Oracle SQL in 10 Minutes - Asim Abbasi
CH1: SQL Basics | CH2: SQL Operators | CH3: SQL Built-in Functions | CH4: SQL Joins | CH5: UPDATE, INSERT & DELETE Statements | CH6: CREATE, ALTER & DROP Statements | CH7: Constraints | CH8: Linking Tables vs Joining Tables | CH9: SQL Statements for Other Database Objects | CH10: SQL Statements for Database Security
Chapter 1: SQL Basics
Anyone knowing English language can easily imagine what the output of this statement would look like. The output will be three fields with all the records from address_book table. So you completed your first SQL statement.
Figure 3: The SELECT Statement is used to query or
retrieve information.
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The SELECT statement as the name says is used to extract data from Oracle Database. The syntax for the simplest SELECT statement is as follows.
SELECT column_name1, column_name2, …
FROM table_name1;
Example:
SELECT *
FROM emp;
This command will display all the fields of the table emp and all of the
records.
Example:
SELECT ename, sal
FROM emp
WHERE sal > 2000;
The result of this statement will be only two columns of emp table and
only those records where salary is greater than 2000.
Example:
SELECT ename, salary
FROM emp
WHERE sal > 2000
ORDER BY ename;
The output of this statement will be exactly the same as the one above
except that the output will be sorted based on ename column.
Chapter 1: Overview
CH1: SQL Basics | CH2:
SQL Operators |
CH3: SQL Built-in Functions | CH4:
SQL Joins | CH5:
UPDATE, INSERT & DELETE Statements |
CH6: CREATE, ALTER & DROP Statements | CH7:
Constraints | CH8:
Linking Tables vs Joining Tables | CH9:
SQL
Statements for Other Database Objects | CH10:
SQL Statements for
Database Security Share with others: