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Skip Slave Counter with GTID_MODE ON #ERROR 1858 (HY000)

With generic asynchronous MySQL Replication we often use skip_slave_counter to tackle / skip anonymous transactions which creates errors or halt MySQL Replication. But if we try to skip slave counter whilst GTID_MOD is ON we get following error. ERROR 1858 (HY000): sql_slave_skip_counter can not be set when the server is running with @@GLOBAL.GTID_MODE = ON. […]

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GTID based Asynchronous Replication in MySQL 8

MySQL replication by default is asynchronous. The master writes events to its binary log but does not know whether or when a slave has retrieved and processed them. With asynchronous replication, if the master crashes, transactions that it has committed might not have been transmitted to any slave. Consequently, failover from master to slave in […]

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MySQL and memory Allocators malloc, tcmalloc and jemalloc

Memory Allocation in UNIX: UNIX uses C dynamic memory allocation libraries for memory allocation. Namely malloc, realloc, calloc and free   are used.  Functions of these liberaries are given below.   Function Description malloc allocates the specified number of bytes realloc Increases or decreases the size of the specified block of memory. Reallocates it if needed calloc allocates the specified number […]

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Deprecated variables in MySQL 8

The following system variables, status variables, and options have been deprecated in MySQL 8.0. Deprecated : expire_logs_days: Purge binary logs after this many days. Added: binlog_expire_logs_seconds: Sets the binary log expiration period in seconds.This is to replace the expire_logs_days. Deprecated : innodb_undo_tablespaces: The number of tablespace files that rollback segments are divided between. Deprecated as […]

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MySQL 8 Invisible Indexes

Invisible Indexes Invisible indexes is new feature added in MySQL 8.0. This feature can help us to mark an index as   unavailable for use by optimizer. This means that index will still be maintained and kept  up to date  in metadata dictionary as data is modified. These marked indexes are not permitted to be used […]