How to Select Just One Row In Oracle By Row ID?

To select just one row in Oracle by row ID, you can use the following code:

1
2
3

SELECT *
FROM your_table
WHERE rowid = 'insert_row_id_here';

Replace 'your_table' with the table name you want to select from, and 'insert_row_id_here' with the actual row ID value.

This query will return all columns of the row with the specified row ID. Make sure the row ID you provide exists in the table, otherwise, no rows will be returned.

Best Oracle Books to Read in 2024

1

Rating is 5 out of 5

Oracle PL/SQL by Example (The Oracle Press Database and Data Science)

Get Book Now

2

Rating is 4.9 out of 5

Oracle Database 12c DBA Handbook (Oracle Press)

Get Book Now

3

Rating is 4.8 out of 5

Oracle Database Administration: The Essential Refe: A Quick Reference for the Oracle DBA

Get Book Now

4

Rating is 4.7 out of 5

Oracle DBA Mentor: Succeeding as an Oracle Database Administrator

Get Book Now

5

Rating is 4.6 out of 5

OCA Oracle Database SQL Exam Guide (Exam 1Z0-071) (Oracle Press)

Get Book Now

6

Rating is 4.5 out of 5

Oracle Database 12c SQL

Get Book Now

7

Rating is 4.4 out of 5

Oracle Autonomous Database in Enterprise Architecture: Utilize Oracle Cloud Infrastructure Autonomous Databases for better consolidation, automation, and security

Get Book Now

How to sort rows in descending order in Oracle?

To sort rows in descending order in Oracle, you can use the ORDER BY clause with the DESC keyword. Here is an example:

SELECT column1, column2, ... FROM your_table ORDER BY column1 DESC;

This query will retrieve rows from the "your_table" table and sort them in descending order based on the values in "column1". You can add additional columns to the ORDER BY clause if you want to sort on multiple columns.

How to combine multiple select statements in Oracle?

To combine multiple select statements in Oracle, you can use the UNION or UNION ALL operator. Here are the steps:

1. Write the first SELECT statement.
2. After the first SELECT statement, add the UNION or UNION ALL operator. UNION: This operator removes duplicate rows from the combined result set. UNION ALL: This operator does not remove duplicate rows from the combined result set.
3. Write the second SELECT statement.
4. Repeat steps 2 and 3 for additional SELECT statements you want to combine.

Here's an example:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15

SELECT column1, column2
FROM table1
WHERE condition1

UNION

SELECT column1, column2
FROM table2
WHERE condition2

UNION

SELECT column1, column2
FROM table3
WHERE condition3;

Note that all SELECT statements must have the same number of columns, and the column types must be compatible.

How to use the IN keyword in Oracle to select rows matching a list of values?

To use the IN keyword in Oracle to select rows matching a list of values, follow the steps below:

1. Start by writing the SELECT statement as you normally would.
2. After the WHERE clause, add the column name you want to match against followed by the IN keyword.
3. Inside parentheses, provide a list of values you want to match against, separated by commas.

Example:

Let's say you have a table named "employees" with columns "employee_id" and "name". You want to select rows where the employee_id is either 1, 3, or 5.

1
2
3

SELECT employee_id, name
FROM employees
WHERE employee_id IN (1, 3, 5);

This query will retrieve the rows matching the employee_ids 1, 3, and 5 from the "employees" table.

How to perform an inner join in Oracle?

To perform an inner join in Oracle, you can use the SQL syntax INNER JOIN or the JOIN keyword. Here is an example:

1
2
3

SELECT table1.column1, table1.column2, table2.column1
FROM table1
INNER JOIN table2 ON table1.common_column = table2.common_column;

In this example, table1 and table2 are the two tables you want to join, and common_column is the column that exists in both tables and is used to establish the join relationship.

You can specify the columns you want to select from both tables using the table_name.column_name format.

If you prefer using the JOIN keyword, the syntax would be as follows:

1
2
3

SELECT table1.column1, table1.column2, table2.column1
FROM table1
JOIN table2 ON table1.common_column = table2.common_column;

Both INNER JOIN and JOIN will produce the same result.

How to filter rows based on a condition in Oracle?

To filter rows based on a condition in Oracle, you can use the WHERE clause in a SELECT statement. The WHERE clause allows you to specify a condition that the rows must meet in order to be included in the result set.

Here is the basic syntax of a SELECT statement with a WHERE clause:

1
2
3

SELECT column1, column2, ...
FROM table_name
WHERE condition;

In the WHERE clause, you can use comparison operators (such as "=", "<>", "<", ">", "<=", ">=") to compare the values in a column with a specified value or expression. You can also use logical operators (such as AND, OR, and NOT) to combine multiple conditions.

Here are a few examples:

1. Select all customers with a balance greater than 1000:

1
2
3

SELECT * 
FROM customers 
WHERE balance > 1000;

1. Select all orders placed in the year 2021:

1
2
3
4

SELECT * 
FROM orders 
WHERE order_date >= TO_DATE('01-JAN-2021', 'DD-MON-YYYY') 
  AND order_date < TO_DATE('01-JAN-2022', 'DD-MON-YYYY');

1. Select all employees whose job title is either 'Manager' or 'Assistant':

1
2
3

SELECT * 
FROM employees 
WHERE job_title = 'Manager' OR job_title = 'Assistant';

These are just a few examples, and you can customize the conditions based on your specific requirements.