Question

晚上好，

当我使用sqlite浏览器运行我的代码模拟时，即使sqlfiddle显示我的代码工作正常，我也能得到正确的结果。但是当我在php pdo中尝试它时显示错误的结果。

这里是sqlfiddle http://sqlfiddle.com/#!5/9644d/1＆lt; ~~在这个链接中工作正常，但是在php pdo中它没有工作......

这是我用来调用我的数据的代码

SELECT id,name,type,MIN(price) as price,MAX(best_selling) as best_selling 
FROM Perf 
GROUP BY type,name 
ORDER BY best_selling DESC, id ASC

如果有替代方法可以调用我的代码，那么它将正常工作。

我的计划是获得 best_selling 的结果，数据库中可用最低价格，然后按类型和名称分组，然后按排序best_selling 首先显示

Answer 1

在SQLFiddle中有测试数据:)这引起了我的注意 - 谢谢 - 它确实帮助了我:)）

我在这里将所有信息加载到SQLite数据库中:)我使用SQLite IDE。它工作正常并导出ok：）

有效的SQL查询？

我使用SQLlite IDE检查您的查询。嗯，这不是一个有效的查询; - /为什么？

您使用'group by'子句。那没问题。但是，所有其他所选列必须在组函数中才能成为其他SQL引擎中的有效SQL。

考虑到这一点：我决定通过在查询中包含“min”和“max”值来更轻松地调试查询。

请参阅：http://sqlfiddle.com/#!5/9644d/2了解我实际使用的有效SQLite SQL查询。我也在PHP中使用了这个查询。

使用SQL查询

所以：这是我使用的查询：

SELECT min(id) AS id_start, 
            max(id) AS id_end, 
            name,
            type,
            MIN(price)            as min_price,
            MAX(price)            as max_price,
            MAX(best_selling) as best_selling 
FROM Perf
GROUP BY type,
         name 
ORDER BY best_selling DESC, 
                 id_end ASC

结果：

id_start    id_end  name    type    min_price   max_price   best_selling
102 103 another_thing   plastic 10  30  2
101 105 something   glass   20  50  2
100 100 random322312    glass   20  20  1
104 104 something   stone   30  30  1
106 106 random_12321312 glass   111 111 1
107 107 random_12321512 glass   111 111 1
108 108 random_1232312  glass   111 111 1
109 109 random_1236312  glass   111 111 1
97  97  rand55312   glass   20  20  1
98  98  ran62312    glass   20  20  1
99  99  ran44232312 glass   20  20  1

以上SQLite IDE代码有效......

现在我们需要显示使用SQLite数据库的PDO版本返回相同的结果......

使用PDO将工作SQL转换为PHP ...

从这里开始，只需在IDE中转换工作SQL代码即可使用PDO进入PHP的工作代码。这不是很难吗？

0）创建有效的SQLite数据库的有效PDO连接。见下面的出口。

1）复制SQL：

    $sql = "SELECT min(id) AS id_start, 
                max(id) AS id_end, 
                name,
                type,
                MIN(price)            as min_price,
                MAX(price)            as max_price,
                MAX(best_selling) as best_selling 
            FROM Perf
            GROUP BY type,
                     name 
            ORDER BY best_selling DESC, 
                    id_end ASC";

    $stmt = $dbPdo->prepare($sql);  
    $stmt->execute();

-----结果---

查看所有结果：

// get them all
$stmt->fetchAll();

结果：

┌──────────────────────────────────────────────────────────────────────────────┐
│                              $stmt->fetchAll()                               │
└──────────────────────────────────────────────────────────────────────────────┘
array (11) [
    array (7) [
        'id_start' => string (3) "102"
        'id_end' => string (3) "103"
        'name' => string (13) "another_thing"
        'type' => string (7) "plastic"
        'min_price' => string (2) "10"
        'max_price' => string (2) "30"
        'best_selling' => string (1) "2"
    ]
    array (7) [
        'id_start' => string (3) "101"
        'id_end' => string (3) "105"
        'name' => string (9) "something"
        'type' => string (5) "glass"
        'min_price' => string (2) "20"
        'max_price' => string (2) "50"
        'best_selling' => string (1) "2"
    ]
    array (7) [
        'id_start' => string (3) "100"
        'id_end' => string (3) "100"
        'name' => string (12) "random322312"
        'type' => string (5) "glass"
        'min_price' => string (2) "20"
        'max_price' => string (2) "20"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (3) "104"
        'id_end' => string (3) "104"
        'name' => string (9) "something"
        'type' => string (5) "stone"
        'min_price' => string (2) "30"
        'max_price' => string (2) "30"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (3) "106"
        'id_end' => string (3) "106"
        'name' => string (15) "random_12321312"
        'type' => string (5) "glass"
        'min_price' => string (3) "111"
        'max_price' => string (3) "111"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (3) "107"
        'id_end' => string (3) "107"
        'name' => string (15) "random_12321512"
        'type' => string (5) "glass"
        'min_price' => string (3) "111"
        'max_price' => string (3) "111"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (3) "108"
        'id_end' => string (3) "108"
        'name' => string (14) "random_1232312"
        'type' => string (5) "glass"
        'min_price' => string (3) "111"
        'max_price' => string (3) "111"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (3) "109"
        'id_end' => string (3) "109"
        'name' => string (14) "random_1236312"
        'type' => string (5) "glass"
        'min_price' => string (3) "111"
        'max_price' => string (3) "111"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (2) "97"
        'id_end' => string (2) "97"
        'name' => string (9) "rand55312"
        'type' => string (5) "glass"
        'min_price' => string (2) "20"
        'max_price' => string (2) "20"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (2) "98"
        'id_end' => string (2) "98"
        'name' => string (8) "ran62312"
        'type' => string (5) "glass"
        'min_price' => string (2) "20"
        'max_price' => string (2) "20"
        'best_selling' => string (1) "1"
    ]
    array (7) [
        'id_start' => string (2) "99"
        'id_end' => string (2) "99"
        'name' => string (11) "ran44232312"
        'type' => string (5) "glass"
        'min_price' => string (2) "20"
        'max_price' => string (2) "20"
        'best_selling' => string (1) "1"
    ]
]
▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄
Called from K:\developer\webapps\testitapp\tests\systest\phpunit\sogQ46632424_sqlite.ph

// ............................... 将使用的导出的SQLite数据库：

--
-- File generated with SQLiteStudio v3.1.1 on Mon Oct 9 00:24:55 2017
--
-- Text encoding used: System
--
PRAGMA foreign_keys = off;
BEGIN TRANSACTION;

-- Table: Perf
CREATE TABLE Perf
    ("id" TEXT, "name" TEXT, "type" TEXT, "price" INTEGER, "best_selling" INTEGER);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('97', 'rand55312', 'glass', 20, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('98', 'ran62312', 'glass', 20, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('99', 'ran44232312', 'glass', 20, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('100', 'random322312', 'glass', 20, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('101', 'something', 'glass', 20, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('102', 'another_thing', 'plastic', 10, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('103', 'another_thing', 'plastic', 30, 2);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('104', 'something', 'stone', 30, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('105', 'something', 'glass', 50, 2);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('106', 'random_12321312', 'glass', 111, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('107', 'random_12321512', 'glass', 111, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('108', 'random_1232312', 'glass', 111, 1);
INSERT INTO Perf (id, name, type, price, best_selling) VALUES ('109', 'random_1236312', 'glass', 111, 1);

COMMIT TRANSACTION;
PRAGMA foreign_keys = on;

php pdo sqlite在sqlfiddle中显示错误结果它显示ok

1 个答案:

有效的SQL查询？

使用SQL查询

以上SQLite IDE代码有效......

使用PDO将工作SQL转换为PHP ...

查看所有结果：

结果：