Question

我在Netezza，DB2和PostgreSQL数据库中有几个表，我需要对其进行协调，我们提出的最佳方法是在所有3个数据库的所有NUMERIC Table列上执行SUM（）。

有没有人能够快速而简单地找到所有COLUMNS，这些COLUMNS是NUMERIC或INTEGER或BIGINT，然后在所有这些上运行SUM（）？

为了比较结果，我也可以手动完成，或者如果某人有办法在公共表中捕获这些结果并自动检查SUM中的差异？

Answer 1

对于DB2，您可以使用此元数据来帮助您找出每列的数据类型

SELECT
               COLUMN_NAME || ' ' || REPLACE(REPLACE(DATA_TYPE,'DECIMAL','NUMERIC'),'CHARACTER','VARCHAR') || 
               CASE 
                              WHEN DATA_TYPE = 'TIMESTAMP' THEN '' 
                              ELSE
                                             ' (' ||
                                             CASE 
                                                            WHEN CHARACTER_MAXIMUM_LENGTH IS NOT NULL THEN CAST(CHARACTER_MAXIMUM_LENGTH AS VARCHAR(30))
                                                            WHEN NUMERIC_PRECISION IS NOT NULL THEN CAST(NUMERIC_PRECISION AS VARCHAR(30)) || 
                                                                           CASE 
                                                                                          WHEN NUMERIC_SCALE = 0 THEN ''
                                                                                          ELSE ',' || CAST(NUMERIC_SCALE AS VARCHAR(3)) 
                                                                           END
                                                            ELSE ''
                                             END || ')'
               END || ',' "SQLCOL",
               COLUMN_NAME,
               DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION, NUMERIC_SCALE, ORDINAL_POSITION
FROM SYSIBM.COLUMNS
WHERE TABLE_NAME = 'insert your table name'
AND TABLE_SCHEMA = 'insert your table schema'
ORDER BY ORDINAL_POSITION

Answer 2

对于Netezza，我收到了以下问题：

SELECT 0 AS ATTNUM, 'SELECT' AS SQL
UNION
SELECT ATTNUM, 'SUM(' || ATTNAME || ') AS S_' || ATTNAME || ',' AS COLMN
FROM _V_RELATION_COLUMN RC
WHERE NAME = '<table-name>'
AND FORMAT_TYPE= 'NUMERIC'
UNION
SELECT 10000 AS ATTNUM, ' 0 AS FLAG FROM ' || '<table-name>'
ORDER BY ATTNUM

仍然在寻找如何在DB2和PostgreSQL上实现这一目标。

如何在表中找到所有NUMERIC列并对它们执行SUM（）？

2 个答案: