MySQL 1196: Too many connections.

When encountering the error "1196: Too many connections" in MySQL, follow these steps:

  1. Check the current number of connections:


Run the following command in the MySQL shell to see how many connections are currently open:
SHOW STATUS WHERE `variablename` = 'Threadsconnected';

  1. Identify the source of connections:


Use this command to list all current connections, including the source host:
SHOW PROCESSLIST;

  1. Increase the connection limit temporarily (if possible and applicable):


Check the current limit:
SHOW VARIABLES LIKE "max_connections";
If needed and your system resources allow, increase the number of connections temporarily:
SET GLOBAL maxconnections = limit>;
Replace `` with the new limit value. Be cautious with this step; ensure your server has enough resources to handle the increased limit.

  1. Kill unnecessary or idle connections:


If you identify connections that are idle or not needed, you can terminate them using:
KILL ;
Replace `` with the ID of the thread you want to kill, obtained from the `SHOW PROCESSLIST` output.

These steps should help mitigate the immediate issue. However, it's essential to investigate why the connection limit was reached to prevent future occurrences.

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MySQL 1250: Partition key not allowed.
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MySQL 1244: Cannot create partition.
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MySQL 1240: Partition is corrupted.
MySQL 1241: Cannot shrink partition.
MySQL 1239: Partition needs repair.
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MySQL 1238: Cannot repair partition.
MySQL 1237: Partition is full.
MySQL 1234: Cannot unlock partition.
MySQL 1235: Statement not allowed in partition.
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MySQL 1227: Failed to create partition.
MySQL 1222: Too many partitions.
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MySQL 1225: Duplicate partition name.
MySQL 1224: Partition not empty.
MySQL 1223: Partition key was not found.
MySQL 1221: Cannot delete parent row.
MySQL 1220: Cannot update parent row.
MySQL 1219: Cannot update child row.
MySQL 1216: Cannot delete or update a parent row.
MySQL 1218: Cannot delete child row.
MySQL 1215: Cannot add foreign key constraint.
MySQL 1217: Cannot add child row.
MySQL 1214: Row was updated.
MySQL 1213: Deadlock found when trying to get lock.
MySQL 1208: Failed to drop key.
MySQL 1211: Too many open files.
MySQL 1210: Key already exists.
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MySQL 1204: Cannot update entry.
MySQL 1206: Error in unique key constraint.
MySQL 1207: Duplicate key found.
MySQL 1205: Error in foreign key constraint.
MySQL 1203: Cannot insert entry.
MySQL 1202: Cannot delete entry.
MySQL 1199: Statement failed due to index.
MySQL 1200: Index is corrupted.
MySQL 1201: Duplicate key value.
MySQL 1198: Error closing file.
MySQL 1193: Statement failed due to table.
MySQL 1197: Failed to open file.
MySQL 1175: Statement not allowed in schema.
MySQL 1196: Too many connections.
MySQL 1194: Table needs repair.
MySQL 1195: Table is corrupted.
MySQL 1192: Statement failed due to view.
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