PSLine2000Documentation/Queries/MachineNames_Crosstab1.md

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# MachineNames_Crosstab1
Analysis generated on: 4/2/2025 10:01:54 AM
---
## SQL Statement
```sql
TRANSFORM Count([WC2]) AS [The Value]
SELECT [MachineName], Count([WC2]) AS [Row Summary]
FROM MachineNames
GROUP BY [MachineName]
PIVOT [WC2];
```
## Dependencies
- [[Tables/MachineNames]]
## Parameters
- *None*
## What it does
**SQL Code Explanation**
==========================
### Table Structure and Data Assumptions
This SQL code is assumed to be part of a larger query that operates on a database table named `MachineNames`. The table contains columns related to machine names, including at least one column named `[WC2]`, which is used as the input for a pivot operation.
### Code Breakdown
---------------
#### 1. `TRANSFORM Count([WC2]) AS [The Value]`
This line transforms the count of values in the `[WC2]` column into a new value with the alias `[The Value]`. This step prepares the data for the pivot operation by aggregating the counts.
#### 2. `SELECT [MachineName], Count([WC2]) AS [Row Summary] FROM MachineNames GROUP BY [MachineName]`
This section selects the `MachineName` column and aggregates the count of values in the `[WC2]` column using the `GROUP BY` clause. The resulting data is then filtered to only include unique machine names.
#### 3. `PIVOT [WC2];`
Finally, this line pivots the aggregated counts for each machine name into separate columns based on the original `[WC2]` values. However, there seems to be a discrepancy in the code - it should be `PIVOT [The Value]` instead of `[WC2]`. Assuming the correct code is used:
* The pivot operation transforms the aggregated counts into separate column headers.
* Each machine name becomes a new row with its corresponding values as separate columns.
**Example Output**
-----------------
Assuming the original data in `MachineNames` table looks like this:
| MachineName | WC2 |
|-------------|-----|
| Mach1 | 10 |
| Mach2 | 20 |
| Mach3 | 30 |
The transformed output would look something like this:
| MachineName | Mach1 | Mach2 | Mach3 |
|-------------|-------|-------|-------|
| Mach1 | 10 | NULL | NULL |
| Mach2 | NULL | 20 | NULL |
| Mach3 | NULL | NULL | 30 |
In this example, the pivot operation has transformed each machine name into a separate row with its corresponding values as separate columns.