![]() ![]() ![]() If you want to be able to use Informix or DB2. Should not use column names that are longer than 18 characters Information crash-me can provide is that you Possible feature, but it is still reasonably comprehensive, You can use the MySQLĬrash-me program to find functions, types,Īnd limits that you can use with a selection of database Which SQL servers it must work with, and then determine whatįeatures those servers support. To make a complex application portable, you need to determine That is, they haveĭifferent design compromises that lead to different behavior. If you want an application that is fast with manyĭatabase systems, it becomes even more difficult.Īll database systems have some weak points. Inserts, but becomes more difficult the more capabilities you Is very easy to achieve portability for very simple selects and #MYSQL OPTIMIZER TURN OFF PORTABLE#SQL, it takes work to write portable database applications. For more information, seeħ.1.2. Designing Applications for Portabilityīecause all SQL servers implement different parts of standard This is an uncommon bottleneck for most systems, but one to beįor instant notification of system bottlenecks subscribe to the The CPU cache, main memory bandwidth becomes a bottleneck. When the CPU needs more data than can fit in With small tables, speed is usually not the problem. The amount of memory is the most common limiting factor. When we have the data in main memory, we need to This isĮasier to optimize than seeks because you can read in parallelĬPU cycles. With modern disks, oneĭisk delivers at least 10–20MB/s throughput. Time is to distribute the data onto more than one disk.ĭisk reading and writing. This time improves slowly with new disks and is very Lower than 10ms, so we can in theory do about 100 seeks a With modern disks, the mean time for this is usually It takes time for the disk to find a piece ofĭata. Remember, however, that there are alwaysĪdditional ways to make the system even faster, although they mayĭisk seeks. This chapter tries to explain and give some examples of different Your system to become, the more you must know about it. Knowledge of your system or application, the more optimal you want Although it mayīe possible to perform some local optimizations with little Understanding of the entire system to be optimized. Optimization is a complex task because ultimately it requires How MySQL Uses Internal Temporary Tables 7.5.10. How MySQL Uses Threads for Client Connections 7.5.8. How Compiling and Linking Affects the Speed of MySQL 7.5.7. Controlling Query Optimizer Performance 7.5.4. System Factors and Startup Parameter Tuning 7.5.2. Drawbacks to Creating Many Tables in the Same Database 7.5. MyISAM Index Statistics Collection 7.4.8. Make Your Data as Small as Possible 7.4.3. Optimizing SELECT and Other Statements 7.2.1. Designing Applications for Portability 7.1.3. MySQL Design Limitations and Tradeoffs 7.1.2. ![]()
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