参考  http://blog.csdn.net/github_26672553/article/details/51889847

SELECT customer_id,group_id,email,SUM(grand_total) AS total_amount,COUNT(*) AS orders_num   
FROM sales_flat_order_grid      
LEFT JOIN customer_entity  ON customer_entity.entity_id = sales_flat_order_grid.customer_id     
WHERE `status`='complete' AND customer_id IS NOT NULL  AND customer_entity.group_id = 1   
GROUP BY customer_id      
ORDER BY orders_num DESC 

需求：

我只需要orders_num这列值 >= 5的数据。

方法：在这个select外面 在套一个 select

SELECT SS.* FROM (  
    #...上面那个SQL    
)SS  
where SS.orders_num >=5   

最终如下：

SELECT SS.* FROM (  
    SELECT customer_id,group_id,email,SUM(grand_total) AS total_amount,COUNT(*) AS orders_num   
    FROM sales_flat_order_grid      
    LEFT JOIN customer_entity  ON customer_entity.entity_id = sales_flat_order_grid.customer_id     
    WHERE `status`='complete' AND customer_id IS NOT NULL  AND customer_entity.group_id = 1   
    GROUP BY customer_id      
    ORDER BY orders_num DESC      
)SS  
where SS.orders_num >=5  

优化前：

select  (select t.gc_name from shop_goods_class as t where t.gc_id=(select two_gc.gc_parent_id from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) ) as oneName,

(select two_gc.gc_name from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) as twoGcName,
 (select two_gc.gc_id from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) as id,
 (select two_gc.gc_parent_id from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) as pid,
gc.gc_name as threeGcName from shop_goods_class as gc where   (select two_gc.gc_name from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) is not null



优化后的sql：
select * from (select  (select t.gc_name from shop_goods_class as t where t.gc_id=(select two_gc.gc_parent_id from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) ) as oneName,
(select two_gc.gc_name from shop_goods_class as two_gc where two_gc.gc_id=gc.gc_parent_id) as twoGcName,
gc.gc_name as threeGcName from shop_goods_class as gc )tt
where tt.twoGcName is not null  and tt.oneName is not null

 

$where['userid|uname'] = ['like',"%".$keyword."%"];
 
$list = Db::name('member')->where($where)->order('mid desc')->limit(15)->select(); 

$where['field'] = ['neq','not null']; //不为空
$where['field'] = null;       //null

$where = array();
        $where['id'] = array('in', $uid_str);
        $res = $this->db2->name('user')->where($where)->select();

# coding:utf-8

import numpy as np

x = np.array([[1, -1], [-1, 1]])
print(x)
"""
[[ 1 -1]
 [-1  1]]
"""

# 将第一列中的-1替换程100
x[:, 0] = np.where(x[:, 0] == -1, 100, x[:, 0])
print(x)
"""
[[  1  -1]
 [100   1]]
"""

# 将第一行中的-1替换成200
x[0, :] = np.where(x[0, :] == -1, 200, x[0, :])
print(x)
"""
[[  1 200]
 [100   1]]
"""

# 将除去100和200之外的所有元素替换成300
x = np.where((x != 100) & (x != 200), 300, x)
print(x)
"""
[[300 200]
 [100 300]]
"""

# 将100和200替换成400
x = np.where((x == 100) | (x == 200), 400, x)
print(x)
"""
[[300 400]
 [400 300]]
"""

参考链接