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January 2017
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MySQL : ERROR 1217 (23000): Cannot delete or update a parent row: a foreign key constraint fails

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While I’ve been working with MySQL host more frequently, I’d to drop a database due to storage space constraint. When I’m executing the drop command,it showing an error that

"ERROR 1217 (23000): Cannot delete or update a parent row: a foreign key constraint fails"

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Some strange error but not severe since MySQL database is [...]

MySQL : How to create multiple root user (Super admin)

I have a situation to create multiple root users for managing a large Database. I used to execute ‘ grant all *. user@localhost identified by ‘password’ ” to create super users earlier. But I realized that these users can’t alter the existing users permission set even though they can create same privilege set users.

Knowing [...]

Renaming database having innodb tables/Moving inoodb database

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While you are working with Huge MySQL data, you will need to switch your tables to innodb storage engine to get fast transactions performance. Suppose if you have a requirement to restore the database which having +>400G volume and the target server having the same database name exist. So if you restore the database, the [...]

MySQL : Managing Sleeping / Active connections to avoid “too many connections” error

One the busiest MySQL server recently had an issue with “SQL Error 1040: Too Many Connections”. This server has already set 1000 connections limit which I believe quite enough to handle our platform. But we were getting frequent MySQL outage due to this kind of errors. We know that it’s a application leakage issue and [...]

MySQL : Improving performance through thread_cache_size

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We can improve the MySQL server performance at the best level if it is being used for read operations most of the time. Based of the Database server analysis, it is observed that more than 70% of traffic is being used “select” statements ie read operations. So I increased the “query_cache_size” and found faster throughput [...]

How do I enable huge TLB on MySQL server

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To get maximum hardware acceleration via reducing Tranaction Lockside Buffer (TLB) ie Applications that perform a lot of memory accesses may obtain performance improvements by using large pages due to reduced Translation Lookaside Buffer (TLB) misses.

Here is the quick guide to setup this one for a single core 3.7G RAM AWS instance for [...]