Here are some common DB performance issues and their solutions:
1. Slow queries: Queries that take a long time to execute can cause the database to become unresponsive. One solution is to optimize the queries by using indexes and avoiding unnecessary joins.
2. Too many connections: When too many connections are established to a database, it can cause performance issues. One solution is to limit the number of connections or to use a connection pool.
3. Poor indexing: Without proper indexing, the database may have to scan the entire table to find the data it needs, which can slow down performance. One solution is to create indexes on the columns used in frequently executed queries.
4. Insufficient hardware resources: If the database server does not have enough CPU, memory, or disk resources, it can cause performance issues. One solution is to upgrade the hardware or optimize the configuration of the existing hardware.
5. Locking and blocking: When multiple users access the same data, locking and blocking can occur, causing performance issues. One solution is to use row-level locking instead of table-level locking.
6. Fragmentation: Over time, data can become fragmented, causing performance issues. One solution is to perform regular maintenance tasks, such as defragmenting the database.
7. Poorly designed schema: A poorly designed database schema can cause performance issues. One solution is to redesign the schema to better reflect the application's data access patterns.
8. Inefficient use of database connections: If an application does not use database connections efficiently, it can cause performance issues. One solution is to use connection pooling or optimize the code that accesses the database.