在 Oracle 中转换 Table?
Pivot Table in Oracle?
我有一个包含许多列的 table,用于指定错误是否有效。我需要以这样一种方式输出,即指定错误的列名称作为行以及每个错误的有效和无效字段的计数。
下面类似输入和预期输出的示例
id name txn_column_name flag1 flag2 flag3
1 Resident Count resident_ct Y Y N
2 Incident Count incident_ct Y Y Y
3 Facility Status facil_stat N N N
需要输出
Col1_name Y_Count N_Count
flag1 2 1
flag2 2 1
flag3 1 2
我们可以在这里尝试使用 Oracle 的 UNPIVOT
运算符:
SELECT
flag AS Col1_name,
COUNT(CASE WHEN val = 'Y' THEN 1 END) AS Y_Count,
COUNT(CASE WHEN val = 'N' THEN 1 END) AS N_Count
FROM yourTable
UNPIVOT
(
val FOR (flag) IN (
flag1 AS 'flag1',
flag2 AS 'flag2',
flag3 AS 'flag3'
)
)
GROUP BY
flag
ORDER BY
flag;
另一个直接的选项使用一系列联合:
SELECT
'flag1' AS Col1_name,
COUNT(CASE WHEN flag1 = 'Y' THEN 1 END) AS Y_Count,
COUNT(CASE WHEN flag1 = 'N' THEN 1 END) AS N_Count
FROM yourTable
UNION ALL
SELECT 'flag2', COUNT(CASE WHEN flag2 = 'Y' THEN 1 END),
COUNT(CASE WHEN flag2 = 'N' THEN 1 END)
FROM yourTable
UNION ALL
SELECT 'flag3', COUNT(CASE WHEN flag3 = 'Y' THEN 1 END),
COUNT(CASE WHEN flag3 = 'N' THEN 1 END)
FROM yourTable
ORDER BY 1;
我有一个包含许多列的 table,用于指定错误是否有效。我需要以这样一种方式输出,即指定错误的列名称作为行以及每个错误的有效和无效字段的计数。
下面类似输入和预期输出的示例
id name txn_column_name flag1 flag2 flag3
1 Resident Count resident_ct Y Y N
2 Incident Count incident_ct Y Y Y
3 Facility Status facil_stat N N N
需要输出
Col1_name Y_Count N_Count
flag1 2 1
flag2 2 1
flag3 1 2
我们可以在这里尝试使用 Oracle 的 UNPIVOT
运算符:
SELECT
flag AS Col1_name,
COUNT(CASE WHEN val = 'Y' THEN 1 END) AS Y_Count,
COUNT(CASE WHEN val = 'N' THEN 1 END) AS N_Count
FROM yourTable
UNPIVOT
(
val FOR (flag) IN (
flag1 AS 'flag1',
flag2 AS 'flag2',
flag3 AS 'flag3'
)
)
GROUP BY
flag
ORDER BY
flag;
另一个直接的选项使用一系列联合:
SELECT
'flag1' AS Col1_name,
COUNT(CASE WHEN flag1 = 'Y' THEN 1 END) AS Y_Count,
COUNT(CASE WHEN flag1 = 'N' THEN 1 END) AS N_Count
FROM yourTable
UNION ALL
SELECT 'flag2', COUNT(CASE WHEN flag2 = 'Y' THEN 1 END),
COUNT(CASE WHEN flag2 = 'N' THEN 1 END)
FROM yourTable
UNION ALL
SELECT 'flag3', COUNT(CASE WHEN flag3 = 'Y' THEN 1 END),
COUNT(CASE WHEN flag3 = 'N' THEN 1 END)
FROM yourTable
ORDER BY 1;