PSLine2000Documentation/Queries/CntlPanel2.md

CntlPanel2

Analysis generated on: 4/2/2025 9:57:30 AM

SQL Statement

SELECT CntlPanel1.Expr1, Last(CntlPanel1.Expr2) AS LastOfExpr2
FROM CntlPanel1
GROUP BY CntlPanel1.Expr1;

Dependencies

• Queries/CntlPanel1

Parameters

• None

What it does

SQL Query Description

Overview

This SQL query retrieves specific information from a table named CntlPanel1 and groups the results by a particular column. The query uses aggregate functions to calculate the last occurrence of another column.

Breakdown

1. SELECT CntlPanel1.Expr1, Last(CntlPanel1.Expr2) AS LastOfExpr2

• This line selects two columns:
  • CntlPanel1.Expr1: All non-aggregated values from this column.
  • Last(CntlPanel1.Expr2) AS LastOfExpr2: The last occurrence of values in CntlPanel1.Expr2, aliased as LastOfExpr2.

2. FROM CntlPanel1

• This line specifies the table from which to retrieve data: CntlPanel1.

3. GROUP BY CntlPanel1.Expr1

• This line groups the results by non-aggregated values in CntlPanel1.Expr1. Each group will contain all rows with the same value for Expr1.
• Since we're grouping by Expr1, SQL will aggregate the last occurrence of Expr2 within each group.

Query Purpose

The query appears to be designed to retrieve a list of unique Expr1 values from the table, along with their corresponding most recent Expr2 values. The result set will contain separate rows for each unique value in Expr1, allowing you to identify and view each value's last observed Expr2.

Assumptions

• The table CntlPanel1 has columns named Expr1 and Expr2.
• The data is structured so that Expr2 values are timestamped, with the most recent values being stored last in the table.
• The database management system supports the use of aggregate functions like Last and allows for aliasing column names.