反向负载率分析:列表展示设备/线路(35kV变压器)、总数量、数量/占比(λmax>0.8、0<λmax≤80%、λmax≤0)。sql语句
时间: 2024-04-30 16:25:11 浏览: 125
假设设备/线路信息存储在名为"device_info"的表中,那么可以使用以下SQL语句进行反向负载率分析:
```
SELECT
device_type,
COUNT(*) AS total_count,
SUM(CASE WHEN lambda_max > 0.8 THEN 1 ELSE 0 END) AS high_load_count,
SUM(CASE WHEN lambda_max > 0 AND lambda_max <= 0.8 THEN 1 ELSE 0 END) AS moderate_load_count,
SUM(CASE WHEN lambda_max <= 0 THEN 1 ELSE 0 END) AS low_load_count,
ROUND(SUM(CASE WHEN lambda_max > 0.8 THEN 1 ELSE 0 END)/COUNT(*)*100,2) AS high_load_percent,
ROUND(SUM(CASE WHEN lambda_max > 0 AND lambda_max <= 0.8 THEN 1 ELSE 0 END)/COUNT(*)*100,2) AS moderate_load_percent,
ROUND(SUM(CASE WHEN lambda_max <= 0 THEN 1 ELSE 0 END)/COUNT(*)*100,2) AS low_load_percent
FROM device_info
WHERE device_type = '35kV变压器'
GROUP BY device_type;
```
该语句会按照设备/线路类型为"35kV变压器"进行分组,并计算该类型设备/线路的总数量、高负载数量、中等负载数量、低负载数量以及占比。其中,λmax>0.8的设备/线路会被归类为高负载,0<λmax≤80%的设备/线路会被归类为中等负载,λmax≤0的设备/线路会被归类为低负载。最后,占比会保留两位小数进行四舍五入。
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