MySQL-连接多个select语句
我最初尝试使用占用太多资源的单个查询获取数据，因此我尝试合并这些查询以减少所需时间。第一个选择本身工作良好，但我想与第二个选择结合使用，以减少所需时间 当前错误：#1241-操作数应包含1列 希望有以下结果MySQL-连接多个select语句,mysql,multiple-select,multiple-select-query,Mysql,Multiple Select,Multiple Select Query,我最初尝试使用占用太多资源的单个查询获取数据，因此我尝试合并这些查询以减少所需时间。第一个选择本身工作良好，但我想与第二个选择结合使用，以减少所需时间 当前错误：#1241-操作数应包含1列 希望有以下结果 +--------------+----------+-------------+---------+-------------+------------+-------------+----------------+ | Description | Maincode | Controlc
+--------------+----------+-------------+---------+-------------+------------+-------------+----------------+
| Description | Maincode | Controlcode | Subcode | Mainbalance | Totaldebit | Totalcredit | Openingbalance |
+--------------+----------+-------------+---------+-------------+------------+-------------+----------------+
| Test Account | 01 | 01 | 123 | 100 | 100 | 0 | 200 |
| Test Account | 01 | 02 | 124 | 100 | 0 | 100 | 0 |
+--------------+----------+-------------+---------+-------------+------------+-------------+----------------+
简单的内部连接和一个简单的数学应该可以做到这一点 |子字符串（voucherdate，1,7）| | :--------------------------- | | 2019-07 | | 2019-07 |
dbfiddleHey@nbk感谢您的友好回复。但是你没有在SELECT语句中加入WHERE部分。我为WHERE添加了一些临界值，但是你的工作我只展示了如何达到你想要的结果。
Subcode Table
+----------+-------------+---------+--------------+
| Maincode | Controlcode | Subcode | Description |
+----------+-------------+---------+--------------+
| 01 | 01 | 123 | Test Account |
| 01 | 02 | 124 | Test Account |
+----------+-------------+---------+--------------+
Voucher Table
+-------------+--------------+---------------+----------+-------------+---------+----------------+-------+--------+
| Voucherdate | Vouchertype | Vouchernumber | Maincode | Controlcode | Subcode | Description | Debit | Credit |
+-------------+--------------+---------------+----------+-------------+---------+----------------+-------+--------+
| 2019-07-13 | BV | 01 | 01 | 01 | 123 | Entering Test | 100 | 0 |
| 2019-07-13 | BV | 01 | 01 | 02 | 124 | Enterting Test | 0 | 100 |
+-------------+--------------+---------------+----------+-------------+---------+----------------+-------+--------+
OpeningBalance Table
+----------+-------------+---------+--------------+---------------+
| Maincode | Controlcode | Subcode | Debitbalance | Creditbalance |
+----------+-------------+---------+--------------+---------------+
| 01 | 01 | 123 | 100 | 0 |
| 01 | 02 | 124 | 100 | 0 |
+----------+-------------+---------+--------------+---------------+
+--------------+----------+-------------+---------+-------------+------------+-------------+----------------+
| Description | Maincode | Controlcode | Subcode | Mainbalance | Totaldebit | Totalcredit | Openingbalance |
+--------------+----------+-------------+---------+-------------+------------+-------------+----------------+
| Test Account | 01 | 01 | 123 | 100 | 100 | 0 | 200 |
| Test Account | 01 | 02 | 124 | 100 | 0 | 100 | 0 |
+--------------+----------+-------------+---------+-------------+------------+-------------+----------------+
CREATE TABLE Subcode
(`Maincode` int, `Controlcode` int, `Subcode` int, `Description` varchar(12))
;
INSERT INTO Subcode
(`Maincode`, `Controlcode`, `Subcode`, `Description`)
VALUES
(01, 01, 123, 'Test Account'),
(01, 02, 124, 'Test Account')
;
CREATE TABLE Voucher
(`Voucherdate` Date, `Vouchertype` varchar(2), `Vouchernumber` int, `Maincode` int, `Controlcode` int, `Subcode` int, `Description` varchar(14), `Debit` int, `Credit` int)
;
INSERT INTO Voucher
(`Voucherdate`, `Vouchertype`, `Vouchernumber`, `Maincode`, `Controlcode`, `Subcode`, `Description`, `Debit`, `Credit`)
VALUES
('2019-07-13', 'BV', 01, 01, 01, 123, 'Entering Test', 100, 0),
('2019-07-13', 'BV', 01, 01, 02, 124, 'Enterting Test', 0, 100)
;
SELECT * FROM Voucher;
CREATE TABLE OpeningBalance
(`Maincode` int, `Controlcode` int, `Subcode` int, `Debitbalance` int, `Creditbalance` int)
;
INSERT INTO OpeningBalance
(`Maincode`, `Controlcode`, `Subcode`, `Debitbalance`, `Creditbalance`)
VALUES
(01, 01, 123, 100, 0),
(01, 02, 124, 100, 0)
;
SELECT
s.Description
,o.Maincode
,o.Controlcode
,o.Subcode
, o.`Debitbalance` Mainbalance
, v.`Debit` + o.`Debitbalance` Totaldebit
, v.`Credit` + o.`Creditbalance` Totalcredit
, v.`Debit` + o.`Debitbalance` -( v.`Credit` + o.`Creditbalance`) Openingbalance
FROM OpeningBalance o inner Join Voucher v
ON o.Maincode = v.Maincode AND o.Controlcode = v.Controlcode AND o.Subcode = v.Subcode
INNER JOIN Subcode s ON o.Maincode = s.Maincode AND o.Controlcode = s.Controlcode AND o.Subcode = s.Subcode
WHERE MONTH(v.voucherdate) <= 7 AND YEAR(v.voucherdate) <= 2019
SELECT (SELECT sc.description AS description,
sc.maincode,
sc.controlcode,
sc.subcode,
( ob.debitbalance - ob.creditbalance ) AS mainbalance
FROM Subcode AS sc
LEFT JOIN OpeningBalance AS ob
ON ( sc.maincode = ob.maincode
AND sc.controlcode = ob.controlcode
AND sc.subcode = ob.subcode )
GROUP BY sc.maincode,
sc.controlcode,
sc.subcode
ORDER BY sc.maincode,
sc.controlcode,
sc.subcode ASC) AS test,
(SELECT Sum(v.debit) AS totaldebit,
Sum(v.credit) AS totalcredit,
( mainbalance + totaldebit - totalcredit ) AS openingbalance
FROM Subcode AS sc
LEFT JOIN Voucher AS v
ON ( sc.maincode = v.maincode
AND sc.controlcode = v.controlcode
AND sc.subcode = v.subcode )
WHERE Substring(v.voucherdate, 1, 7) < '07-2019'
GROUP BY sc.maincode,
sc.controlcode,
sc.subcode
ORDER BY sc.maincode,
sc.controlcode,
sc.subcode ASC) AS test2
SELECT Substring(voucherdate, 1, 7) FROM Voucher