SQL: Find the last name of all employees, without duplicates

Last update on May 30 2022 07:31:13 (UTC/GMT +8 hours)

SQL Basic Select Statement: Exercise-31 with Solution.

From the following table, write a SQL query to find the unique last name of all employees. Return emp_lname.

Sample table: emp_details

Sample Solution:

SELECT DISTINCT emp_lname
FROM emp_details;

Output of the Query:

emp_lname
Saule
Robbin
Sitaraman
Mardy
Foster
Emily
Manuel
Dosio
Gabriel
Snappy
Snares
Dosni

Relational Algebra Expression:

Relational Algebra Tree:

Duration:

Rows:

Cost:

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Previous: From the following table, write a SQL query to find the cheapest item(s). Return pro_name and, pro_price.
Next: From the following table, write a SQL query to find the details of employees whose last name is 'Snares'. Return emp_idno, emp_fname, emp_lname, and emp_dept.

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What is the difficulty level of this exercise?

SQL Server SELECT into existing table.

INSERT INTO dbo.TABLETWO
SELECT col1, col2
  FROM dbo.TABLEONE
 WHERE col3 LIKE @search_key

This assumes there's only two columns in dbo.TABLETWO - you need to specify the columns otherwise:

INSERT INTO dbo.TABLETWO
  (col1, col2)
SELECT col1, col2
  FROM dbo.TABLEONE
 WHERE col3 LIKE @search_key

Database: SQL Server

Ref: https://bit.ly/3y6tpA3