尝试在SQLite3中创建具有多个条件的SQL VIEW
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我想知道它是否有足够的前进来以下面的方式创建一个视图，我的尝试没有按预期工作，
我正在尝试使用以下查询创建另一个视图，该查询在以下条件为真时标识有问题的'grp'：
我对条件的看法的原始描述：
SELECT grp FROM控件WHERE
（'控制1.p值'||'（第二个）'！='控制2.p值'）
要么
（'控制1.p值'||'（第3）'！='控制3.p值'）
要么
（'control 1.p value'||'（4th）'！='control4.p value'）
要么
（'控制1.p值'||'（第5）'！='控制5.p值'）
要么
（'控制1.p值'||'（第6）'！='控制6.p值'）
我尝试了以下期待M2返回：
SELECT grp FROM control_1 WHERE (pvalue || " (2nd)" != (SELECT pvalue from control_2) AND grp = (SELECT grp from control_2));
但即使这个基本步骤也不适合我。
运行下面的代码片段以查看我尝试尝试此操作的表和视图。
th, td {border: 1px solid black;}<div>
<div>CREATE TABLE control (</div>
<div>id INTEGER PRIMARY KEY AUTOINCREMENT,</div>
<div>grp TEXT,</div>
<div>pname TEXT,</div>
<div>pvalue TEXT);</div>
<div></div><br />
<table>
<tr><td colspan="4"><div>control</div></td></tr>
<tr><th>id</th><th>grp</th><th>pname</th><th>pvalue</th></tr>
<tr><td>1</td><td>M1</td><td>d1</td><td>vat</td></tr>
<tr><td>2</td><td>M1</td><td>d2</td><td>vat (2nd)</td></tr>
<tr><td>3</td><td>M1</td><td>d3</td><td>vat (3rd)</td></tr>
<tr><td>4</td><td>M1</td><td>d4</td><td>vat (4th)</td></tr>
<tr><td>5</td><td>M1</td><td>d5</td><td>vat (5th)</td></tr>
<tr><td>6</td><td>M1</td><td>d6</td><td>vat (6th)</td></tr>
<tr><td>7</td><td>M2</td><td>d1</td><td>bin</td></tr>
<tr><td>8</td><td>M2</td><td>d2</td><td>ban (2nd)</td></tr>
<tr><td>9</td><td>M2</td><td>d3</td><td>bin (3rd)</td></tr>
<tr><td>10</td><td>M2</td><td>d4</td><td>bin (4th)</td></tr>
<tr><td>11</td><td>M2</td><td>d5</td><td>bin (5th)</td></tr>
<tr><td>12</td><td>M2</td><td>d6</td><td>bin (6th)</td></tr>
<tr><td>13</td><td>M3</td><td>d1</td><td>haw</td></tr>
<tr><td>14</td><td>M3</td><td>d2</td><td>haw (2nd)</td></tr>
<tr><td>15</td><td>M3</td><td>d3</td><td>ha (3rd)</td></tr>
<tr><td>16</td><td>M3</td><td>d4</td><td>haw (4th)</td></tr>
<tr><td>17</td><td>M3</td><td>d5</td><td>haw (5th)</td></tr>
<tr><td>18</td><td>M3</td><td>d6</td><td>haw (6th)</td></tr>
</table>
<div></div><br />
<div>CREATE VIEW control_1 AS SELECT * FROM control WHERE pname = "d1";</div>
<div></div>
<table>
<tr><th colspan="4">control_1</th></tr>
<tr><th>id</th><th>grp</th><th>pname</th><th>pvalue</th></tr>
<tr><td>1</td><td>M1</td><td>d1</td><td>vat</td></tr>
<tr><td>7</td><td>M2</td><td>d1</td><td>bin</td></tr>
<tr><td>13</td><td>M3</td><td>d1</td><td>haw</td></tr>
</table>
<div></div><br />
<div></div>
<div>CREATE VIEW control_1 AS SELECT * FROM control WHERE pname = "d2";</div>
<div></div>
<table>
<tr><th colspan="4">control_2</th></tr>
<tr><th>id</th><th>grp</th><th>pname</th><th>pvalue</th></tr>
<tr><td>2</td><td>M1</td><td>d2</td><td>vat (2nd)</td></tr>
<tr><td>8</td><td>M2</td><td>d2</td><td>ban (2nd)</td></tr>
<tr><td>14</td><td>M3</td><td>d2</td><td>haw (2nd)</td></tr>
</table>
<div></div><br />
<div>
<div>CREATE VIEW control_1 AS SELECT * FROM control WHERE pname = "d3";</div>
<div></div>
<table>
<tr><th colspan="4">control_3</th></tr>
<tr><th>id</th><th>grp</th><th>pname</th><th>pvalue</th></tr>
<tr><td>3</td><td>M1</td><td>d3</td><td>vat (3rd)</td></tr>
<tr><td>9</td><td>M2</td><td>d3</td><td>bin (3rd)</td></tr>
<tr><td>15</td><td>M3</td><td>d3</td><td>ha (3rd)</td></tr>
</table>
<div></div><br />
<div>
<div>--I create the following as well, but we can see the problems from the 1st three views</div>
<div>CREATE VIEW control_1 AS SELECT * FROM control WHERE pname = "d4";</div>
<div>CREATE VIEW control_1 AS SELECT * FROM control WHERE pname = "d5";</div>
<div>CREATE VIEW control_1 AS SELECT * FROM control WHERE pname = "d6";</div>
</div>答案
我有一个顿悟，我能够弄清楚以下内容：
我创建了两个新的视图如下，我现在得到了我期待的东西。
create view dview as
SELECT
DISTINCT
grp,
(select pvalue from control_1 WHERE control.grp == grp) as d1,
(select pvalue from control_2 WHERE control.grp == grp) as d2,
(select pvalue from control_3 WHERE control.grp == grp) as d3,
(select pvalue from control_4 WHERE control.grp == grp) as d4,
(select pvalue from control_5 WHERE control.grp == grp) as d5,
(select pvalue from control_6 WHERE control.grp == grp) as d6
FROM control;
这是这个新视图的select语句：
select * from dview;
grp d1 d2 d3 d4 d5 d6
---------- ---------- ---------- ---------- ---------- ---------- ----------
M1 vat vat (2nd) vat (3rd) vat (4th) vat (5th) vat (6th)
M2 bin ban (2nd) bin (3rd) bin (4th) bin (5th) bin (6th)
M3 haw haw (2nd) ha (3rd) haw (4th) haw (5th) haw (6th)
开始创建新视图：
create view dview_err as
SELECT * FROM dview WHERE
(d1 || " (2nd)" != d2) OR
(d1 || " (3rd)" != d3) OR
(d1 || " (4th)" != d4) OR
(d1 || " (5th)" != d5) OR
(d1 || " (6th)" != d6);
这是这个新视图的select语句：
select grp from dview_err;
grp
----------
M2
M3
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