PSLine2000Documentation/Queries/CntlPanel2.md

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# CntlPanel2
Analysis generated on: 4/2/2025 9:57:30 AM
---
## SQL Statement
```sql
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.