Database-PHP Read-write Mongodb,shell read and write MongoDB, the two operations, how the data is isolated from each other?

Start the Mongod server first;
Open a Shell client:

Use haha
Db.haha.insert ({' A ': ' AAA '})
Db.haha.find ()
{' A ': ' AAA '} //Added successfully

Open another shell client:

Use haha
Db.haha.find ()//confirm the input you just made
{' A ': ' AAA '} //is valid

As you can see, the shell client is effective.
Here is the PHP code:

$m = new Mongoclient ();
$jihe = $m->db->haha;

$cursor = $jihe->find ();
foreach ($cursor as $item) {
Var_dump ($item); Nothing, empty data
}

Then modify the PHP code to:

$m = new Mongoclient ();
$jihe = $m->db->haha;

$doc = Array (' b ' = ' BBB ');
$jihe->insert ($doc); PHP tries to insert the data itself

$cursor = $jihe->find ();
foreach ($cursor as $item) {
Var_dump ($item); This time only {' B ': ' BBB '} data, no shell set {' A ': ' AAA '}
}

What's going on here? is for the same database-initiated operation. How is the shell client and PHP access so different?

Reply content:

Start the Mongod server first;
Open a Shell client:

Use haha
Db.haha.insert ({' A ': ' AAA '})
Db.haha.find ()
{' A ': ' AAA '} //Added successfully

Open another shell client:

Use haha
Db.haha.find ()//confirm the input you just made
{' A ': ' AAA '} //is valid

As you can see, the shell client is effective.
Here is the PHP code:

$m = new Mongoclient ();
$jihe = $m->db->haha;

$cursor = $jihe->find ();
foreach ($cursor as $item) {
Var_dump ($item); Nothing, empty data
}

Then modify the PHP code to:

$m = new Mongoclient ();
$jihe = $m->db->haha;

$doc = Array (' b ' = ' BBB ');
$jihe->insert ($doc); PHP tries to insert the data itself

$cursor = $jihe->find ();
foreach ($cursor as $item) {
Var_dump ($item); This time only {' B ': ' BBB '} data, no shell set {' A ': ' AAA '}
}

What's going on here? is for the same database-initiated operation. How is the shell client and PHP access so different?

Speculation: The shell is connected to PHP, which is 2 of the haha db database space.
Open a Shell client, enter a command

show dbs

Output results In addition to Haha, is there a db? If yes

$jihe = $m->db->haha;

should read

$jihe = $m->haha->haha;

If it is no, (Bay stretched out) PHP has not touched for many years.

Make sure you're connected to the same server, the same database

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