How to splice strings without duplication?-PHP Tutorial-php.cn

How to splice strings without duplication?

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Release： 2016-07-06 13:53:29

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For example, there is the following data table structure
id lei shuxing miaoshu
1 Elephant has big eyes
2 Elephant has round eyes
3 Elephant has a tall trunk
4 Bear The nose is small
5 The elephant has long legs
6 The bear has thin legs
7 The elephant has a small mouth

The second, third and fourth columns may have n multiple situations. Find a PHP method that can achieve the following combination of requirements. The requirement is that each description is a lei, covering 3 items in shuxing ( Count as many as there are less than three items (such as bears) to generate different descriptions of an animal

Example: The result based on the above data should be

The elephant has big eyes, a high trunk, and long legs
The elephant has round eyes, a high trunk, and long legs
The elephant has big eyes, a tall trunk , with a small mouth
. . .
Since there are so many combinations, it’s impossible to list them all. I hope friends can understand through the above examples

Reply content:

Example: The result based on the above data should be

Builder pattern http://www.runoob.com/design-pattern/builder-pattern.html

<code>select lei,group_concat(concat(shuxing,miaoshu)) result from tb group by lei</code>

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This will return
lei result
The elephant has big eyes, a tall nose, long legs, and a small mouth
The bear has a small nose and thin legs
...
Go back to the background to split the result by commas, and then randomly splice three results
---The above personal opinions, comments are welcome---

Actually, I still don’t quite understand whether the question is about php or sql.
But I feel that sql is not good at solving this kind of problem, so I assume it is a programming problem.

Since I don’t understand PHP, I only provide problem-solving ideas:
1. Query all qualified data according to lei, for example:

<code class="SQL">SELECT lei, shuxing, miaoshu FROM animal
WHERE lei IN ('大象', '熊');</code>

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2. Perform lei operations on the shuxing attribute and the group by attribute in the code, as follows:

<code class="JSON">{
    "大象": {
        "眼睛": ["大大的", "圆圆的"],
        "鼻子": ["高高的"],
        "腿": ["长长的"],
        "嘴": ["小小的"]
    },
    "熊": {
        ...
    }
}</code>

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3. Perform Cartesian product operation on the data in 2, done.

PS: In fact, the table structure is not designed well. It should be split into animal table (animal_id, animal_name) and animal_prop table (animal_prop_id, animal_id, prop_name, prop_desc).

You can use split tables and divide them into three tables. table1: used to record lei information table2: used to record shuxing, the ID of table1 table3:

Used to record the IDs of miaoshu and table2, and use three tables to perform related queries

Dear friends, can anyone help me solve this problem?

Yes, what I mentioned above is an idea
Split tables
and then perform related queries based on the tables
Take out the class separately and build a table
Create another table based on the attributes of the class (1 pair Multiple relationships)

python version:

<code>from collection import defaultdict

anims = defaultdict(lambda : defaultdict(lambda : defaultdict(set)))

for lei, shuxing, miaoshu in db.select('table', ['lei', 'shuxing', 'miaoshu']):
    anims[lei][shuxing].add(miaoshu)
    
# enum all descs
for lei, v1 in anims.items():
    print 'desc lei: ', lei
    shuxings = [(k, list(v)) for k,v in v1.items()]
    shuxing_size = len(shuxings)
    if shuxing_size == 0:
        pass
    elif shuxing_size == 1:
        for i in range(shuxing_size):
            for ii in range(shuxings[i][1]):
                print shuxings[i][0], shuxings[i][1][ii]
    elif shuxing_size == 2:            
        for i in range(shuxing_size):
            for j in range(i+1, shuxing_size):
                for ii in range(shuxings[i][1]):
                    for jj in range(shuxings[j][1]):
                        print shuxings[i][0], shuxings[i][1][ii], shuxings[j][0], shuxings[j][1][jj]
    else:
        for i in range(shuxing_size):
            for j in range(i+1, shuxing_size):
                for k in range(j+1, shuxing_size):
                    for ii in range(shuxings[i][1]):
                        for jj in range(shuxings[j][1]):
                            for kk in range(shuxings[k][1]):
                                print shuxings[i][0], shuxings[i][1][ii], shuxings[j][0], shuxings[j][1][jj], shuxings[k][0], shuxings[k][1][kk]</code>

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