Q
Problem solve Get help with specific problems with your technologies, process and projects.

# The WITH clause

## The UNION of three tables yields multiple rows of the same product_id with different prices and supplier names, and some with no item info. Can we generate a query to return a distinct set of records based on product_id with the cheapest price and the name of the supplier with that cheapest price?

The UNION of three tables yields multiple rows of the same product_id with different prices and supplier names, and some with no item info:

```product_id  supplier  price  iteminfo
widget      Fred       100    info1
widget      Joe         90    NULL
widget      Billy       95    info3```

Can we generate a query to return a distinct set of records based on product_id with the cheapest price and the name of the supplier with that cheapest price? And/or any one of the filled info fields? Or do we need to step up to PL/SQL? Thanks in advance.

If your data were in a simple table, the query you would use involves a correlated subquery:

```select product_id
, supplier
, price
, iteminfo
from simpletable as T
where price =
( select min(price)
from simpletable
where product_id = T.product_id )```

The only thing we have to change to fit your specific circumstances is to replace `simpletable` with a derived table consisting of the result of your UNION:

```select product_id
, supplier
, price
, iteminfo
from (
select ... from table1
union all
select ... from table2
union all
select ... from table3
) as T
where price =
( select min(price)
from (
select ... from table1
union all
select ... from table2
union all
select ... from table3
) as T1
where product_id = T.product_id )```

Note that we had to make this substitution twice. This sure is clumsy, and yes, there is a better way to write this, using the WITH clause:

```with simpletable as
(
select ... from table1
union all
select ... from table2
union all
select ... from table3
)
select product_id
, supplier
, price
, iteminfo
from simpletable as T
where price =
( select min(price)
from simpletable
where product_id = T.product_id )```

This way of "abstracting" the derived table using the WITH clause makes the SQL manageable again. Note that the WITH clause is SQL-99, so not every database system supports it. In Oracle, you need to be on at least Oracle 9i release 2.

## SearchDataManagement

• ### Oracle brings GoldenGate data integration service to cloud

Oracle is making its GoldenGate real time data technology available on its second-generation Oracle Cloud Infrastructure platform...

• ### Era Software raises \$15.25M for enterprise data management

The startup that began as the EraDB time series database is advancing its efforts with new funding and a cloud service for its ...

• ### Dgraph GraphQL database users detail graph use cases

Graph DB vendor Dgraph Labs is expanding its AWS cloud footprint with new regions and adding change data capture capabilities in ...

• ### TigerGraph unveils support for GCP, adds new connectors

Graph database vendor TigerGraph unveiled support for Google Cloud and new connectors to Snowflake and Tableau on April 21 during...

• ### Startup Veezoo emerges from stealth with NLQ-based platform

Aiming to be 'Siri for enterprises,' an analytics startup emerged from stealth with a platform that enables users to interact ...

• ### 15 data science tools to consider using in 2021

Numerous tools are available for data science applications. Read about 15, including their features, capabilities and uses, to ...

## SearchSAP

• ### S/4HANA Cloud SaaS ERP: Buying team overview

SAP's multi-tenant SaaS ERP, S/4HANA Cloud, is a viable choice for companies that need ease in their infrastructure management. ...

• ### SAP forms financial services partnership with Dediq

SAP and financial industry investment firm Dediq are forming a new business unit to develop applications that help banks and ...

• ### Unpatched applications threaten SAP security

Cyberattacks are a significant threat to unpatched, unprotected SAP applications, according to a new threat intelligence report ...

## SearchSQLServer

• ### SQL Server database design best practices and tips for DBAs

Good database design is a must to meet processing needs in SQL Server systems. In a webinar, consultant Koen Verbeeck offered ...

• ### SQL Server in Azure database choices and what they offer users

SQL Server databases can be moved to the Azure cloud in several different ways. Here's what you'll get from each of the options ...

• ### Using a LEFT OUTER JOIN vs. RIGHT OUTER JOIN in SQL

In this book excerpt, you'll learn LEFT OUTER JOIN vs. RIGHT OUTER JOIN techniques and find various examples for creating SQL ...

## TheServerSide.com

• ### Incorporate diversity and inclusion in technology design

DEI in technology is about more than creating a diverse workplace. We talked to a few DEI professionals about how teams build ...

• ### Microsoft previews OpenJDK distro to the delight of devs

In a move meant to attract more Java developers to its Azure cloud and further support the Java community, Microsoft launched a ...

• ### Supreme Court ruling on Java APIs eases developer worries

Now that the Supreme Court has ruled for Google over Oracle in their high-stakes copyright battle over Java APIs, developers can ...

## SearchDataCenter

• ### Nvidia SDK simulates quantum computing circuits on GPU systems

Nvidia edged its way into the quantum computing market with an SDK that simulates quantum circuits by adding horsepower to ...

• ### Programmable processor technology for next-gen data centers

The right processing technology can benefit your data center. Learn about advancements in CPU technologies, recent vendor ...

• ### Data processing units accelerate infrastructure performance

DPUs often run on networking packets to move information in the data center, instead of supporting processing workflows. Get an ...

## SearchContentManagement

• ### Hyland gets digital asset management tech with Nuxeo buy

By acquiring a smaller competitor's digital asset management platform, Hyland looks to build on its 2020 purchase of Alfresco, ...

• ### OpenText releases Cloud Editions content services updates

OpenText CE 21.2 includes federated document compliance that extends to Microsoft Office 365, along with a revamped content ...

As the pandemic disrupts paper workflows, Adobe courts small business users with simple webforms, digital signatures and payments...

## SearchHRSoftware

• ### Shift to HR shared services could save Connecticut millions

By consolidating 17 separate HR operations into one shared service, Connecticut expects to save significantly on costs, most of ...

• ### 10 steps to support your HCM system post go-live

To ensure a new system's success, HR leaders need to develop a plan for how they will support their new HCM system post go-live. ...

• ### Face mask detection a newcomer to employee surveillance

Face mask detection has emerged as another form of employee surveillance technology, and its adoption may be helped indirectly by...

Close