get the data of multiple conn, operations on the same table in a database. Will one conn.commit, affect other conn data operations?
get the data of multiple conn, operations on the same table in a database. Will one conn.commit, affect other conn data operations?
do not use database connection pooling, but the program to operate conn, needs commit, after each operation. When there are concurrent write operations in your application, it will have a certain impact. It is usually given to database connection pooling. It will initialize a certain number of connection instances at the beginning, and it will be automatically assigned to deal with it when you need to use it.
because the cost of creating a connection is high, it is very consuming for us to recreate the connection every time we visit the database.
We can create some connections when the program starts, put them in a collection, get them from the collection when accessing the database, and put them back in the collection after use.
this only consumes performance to create connections when the program starts, and gets connections from memory every time you access the database, which can greatly improve efficiency.
Note:
because of frequent additions and deletions in the pool, it is more efficient to use collection LinkedList
create new connections when all connections in the collection are occupied, but note that the total number of connections
use combined mode / dynamic proxy to handle the method of releasing connections, and when you run the close method, put the connections back into the pool
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