我在Pervasive V11数据库上进行了以下SQL调用。 我正在努力工作，以便每个项目ID只能获得一行。
SELECT
inventory_history.item_id AS 'ItemId',
RTrim(inventory_items.item_name) AS 'Description',
If(RTrim(trx_type) = 'P',SUM(change_quantity),'') AS 'QtyChangeP',
If(RTrim(trx_type) = 'P',SUM(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),'') AS 'CostChangeP',
If(RTrim(trx_type) = 'S',SUM(change_quantity),'') AS 'QtyChangeS',
If(RTrim(trx_type) = 'S',SUM(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),'') AS 'CostChangeS',
If(RTrim(trx_type) = 'A',SUM(change_quantity),'') AS 'QtyChangeA',
If(RTrim(trx_type) = 'A',SUM(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),'') AS 'CostChangeA',
If(RTrim(trx_type) = 'T',SUM(change_quantity),'') AS 'QtyChangeT',
If(RTrim(trx_type) = 'T',SUM(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),'') AS 'CostChangeT',
If(RTrim(inventory_categories.stocked_by_factor) = 'FT',inventory_items.unit_weight,'') AS 'WtPerFt'
FROM
inventory_history
INNER JOIN
inventory_items ON inventory_history.item_id = inventory_items.item_id
INNER JOIN
inventory_categories ON inventory_items.category_id = inventory_categories.category_id
WHERE
trx_date>'20170731'
GROUP BY
inventory_history.item_id, inventory_items.item_name, trx_type, stocked_by_factor, unit_weight;
就像现在一样，如果我没有在Group By子句中列出trx_type，stocked_by_factor或unit_weight，我会收到数据库中的错误。
删除这些字段会导致此错误：
列无效。必须是按列分组：SELECT LIST中的trx_type。
以下是完整SQL调用的示例结果：
ItemId Description QtyChangeP CostChangeP QtyChangeS CostChangeS QtyChangeA CostChangeA QtyChangeT CostChangeT WtPerFt
========================= ================================================== ============================================================================ ============================================================================ ============================================================================ ============================================================================ ============================================================================ ============================================================================ ============================================================================ ============================================================================ ==============
1100SM19050T2C1 1100-H19 LAMI SHIM .050" TYPE 2, CLASS 1 58.2400 890.00 0.0000 0.00 0.0000 0.00 0.0000 0.00 0.000000
1100SM19050T2C1 1100-H19 LAMI SHIM .050" TYPE 2, CLASS 1 0.0000 0.00 58.2400 890.00 0.0000 0.00 0.0000 0.00 0.000000
1100SM19085T2C1 1100-H19 LAMI SHIM .085" TYPE 2, CLASS 1 0.0000 0.00 0.0000 0.00 0.0000 0.00 0.0000 0.00 0.000000
1100SM19085T2C1 1100-H19 LAMI SHIM .085" TYPE 2, CLASS 1 19.8080 208.00 0.0000 0.00 0.0000 0.00 0.0000 0.00 0.000000
1100SM19085T2C1 1100-H19 LAMI SHIM .085" TYPE 2, CLASS 1 0.0000 0.00 19.8080 208.00 0.0000 0.00 0.0000 0.00 0.000000
非常感谢任何帮助。谢谢！
答案 0 :(得分：0)
条件应该是sum()的参数：
sum(If(RTrim(trx_type) = 'P', change_quantity), 0) AS QtyChangeP,
通常，这将使用case：
sum(case when RTrim(trx_type) = 'P' then change_quantity else 0 end) AS QtyChangeP,
答案 1 :(得分：0)
没关系......经过几个小时的绞尽脑汁，答案就在我的面前。我只需要将If（）函数转换为SUM（）函数。
这是工作电话：
SELECT
inventory_history.item_id AS 'ItemId',
RTrim(inventory_items.item_name) AS 'Description',
SUM(If(RTrim(trx_type) = 'P',inventory_history.change_quantity,0)) AS 'QtyChangeP',
SUM(If(RTrim(trx_type) = 'P',(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),0)) AS 'CostChangeP',
SUM(If(RTrim(trx_type) = 'S',inventory_history.change_quantity,0)) AS 'QtyChangeS',
SUM(If(RTrim(trx_type) = 'S',(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),0)) AS 'CostChangeS',
SUM(If(RTrim(trx_type) = 'A',inventory_history.change_quantity,0)) AS 'QtyChangeA',
SUM(If(RTrim(trx_type) = 'A',(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),0)) AS 'CostChangeA',
SUM(If(RTrim(trx_type) = 'T',inventory_history.change_quantity,0)) AS 'QtyChangeT',
SUM(If(RTrim(trx_type) = 'T',(history_cost_01+history_cost_02+history_cost_03+history_cost_04+history_cost_05+history_cost_06+history_cost_07+history_cost_08+history_cost_09+history_cost_10+history_cost_11+history_cost_12),0)) AS 'CostChangeT',
If(RTrim(inventory_categories.stocked_by_factor) = 'FT',inventory_items.unit_weight,'') AS 'WtPerFt'
FROM
inventory_history
INNER JOIN
inventory_items ON inventory_history.item_id = inventory_items.item_id
INNER JOIN
inventory_categories ON inventory_items.category_id = inventory_categories.category_id
WHERE
trx_date>'20170731'
GROUP BY
inventory_history.item_id, inventory_items.item_name, stocked_by_factor, unit_weight;