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Displaying posts with tag: MySQL optimization (reset)
MySQL fragmentation and how to defragment

In a MySQL database, fragmentation can occur over time as data is inserted, updated, and deleted. Fragmentation refers to the inefficient storage and organization of data within database objects, such…

The post MySQL fragmentation and how to defragment first appeared on Change Is Inevitable.

How to store IP (internet protocol) address in MySQL?

Internet Protocol address is a special kind of data. This data does not correspond directly to available MySQL built-in data types. I have seen in many servers, the IP(Internet Protocol) address is stored in CHAR(12), VARCHAR(15), TEXT and so on. 

The dotted-quad notation is just a way of writing for better readability, it is not the original form of raw data. The IP address is a UNSIGNED INTEGERS they are not strings. 

So the question is how we can store the IP addresses with dot in integer columns? The MySQL provides the built-it function to do this operation. The functions are given below:

For IPv4 addresses:

mysql> select inet_aton('');

| inet_aton('') |
|             2130706433 | …
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Indexing 101: Optimizing MySQL queries on a single table

I have recently seen several cases when performance for MySQL queries on a single table was terrible. The reason was simple: the wrong indexes were added and so the execution plan was poor. Here are guidelines to help you optimize various kinds of single-table queries.

Disclaimer: I will be presenting general guidelines and I do not intend to cover all scenarios. I am pretty confident that you can find examples where what I am writing does not work, but I am also confident that it will help you most of the time. Also I will not discuss features you can find in MySQL 5.6+ like Index Condition Pushdown to keep things simple. Be aware that such features can actually make a significant difference in query response time (for good or for bad).

What an index can do for you

An index can perform up to 3 actions: filter, sort/group and cover. While the first 2 actions are self-explanatory, not everyone may know what …

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MySQL – Choose exact numeric data type

When we use a relational database system, we should know some important things. Numeric data type is very essential for a table. Here I describe some important points of Numeric Data type in MySQL:

MySQL has 9 numeric data types

  • Floating Point:  FLOAT, DOUBLE
  • Fixed Point:      DECIMAL
  • Other:              BIT, (ENUM maybe)‫‏‬

Some poor design:

  • INT(1)‫‏‬
  • no UNSIGNED used
  • DECIMAL(31,0)‫‏‬

INT(1) – 1 does not mean 1 digit.   (1) represents client output display format only. INT is 4 Bytes. TINYINT is 1 Byte …

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Showing entries 1 to 4