Error code
MySQL 1040
MYSQL1040
Database Error Code· An error code returned by a database server such as PostgreSQL or MySQL.
What it means
Too many connections — the server has reached its connection limit.
How to fix it
- Add a connection pool (e.g. ProxySQL or application-level pooling) to multiplex connections.
- Increase max_connections in my.cnf and restart MySQL.
Not affiliated with MySQL. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More MySQL codes
- 1044Access denied for user to database — missing GRANT
- 1045Access denied for user — wrong credentials
- 1048Column cannot be null — a required column received a NULL
- 1050Table already exists — CREATE TABLE failed because the name is taken
- 1051Unknown table — a DROP or query referenced a table that does not exist
- 1054Unknown column — the column name is not defined on the table
- 1062Duplicate entry for key — unique constraint violated
- 1064SQL syntax error — the query contains invalid SQL
- 1136Column count does not match value count — INSERT column and value lists differ
- 1146Table does not exist — the named table is missing
- 1205Lock wait timeout exceeded — a lock could not be acquired in time
- 1213Deadlock found when trying to get lock — two transactions blocked each other