Performance Optimization On Tobacco Planting Spatial Database Based On ORACLE

Flue-cured tobacco is an important cash crop. As the one of the state-planned economy industries, flue-cured tobacco has the characteristics of highly monopoly and rich profit, which has been closely related to industry, agriculture, commerce and so on. On account of China’s economic development and foreign trade are deeply influenced by the development of tobacco industry. So tobacco industry has played a considerably significant role in national economy. As a consequence, flue-cured tobacco was widely planted across the country.Detailed information about tobacco planting can be commendably described by the spatial and attribute data. In the traditional case, the data of tobacco planting is stored and administrated in the way of document. However, with the continuous increase of spatial data, customer requirements for data access become more and more difficult to be satisfied by file management way. Due to large amounts of data can been well handle by the relational database systems, so the management of spatial data using a relational database system is a good choice. In this case, Oracle Spatial Database Engine was proposed. With the engine, spatial data in Oracle database can been quickly and efficiently stored, accessed and analyzed. Therefore, Oracle database is a good way to process spatial data.In the present study, data about land using status of tobacco planting, data about tobacco purchased situation in recent years and data about laboratory analysis of soil samples of formulated fertilization, this three data sources consisted of all the spatial data of tobacco planting. The spatial and attribute data can be obtained by superposition, correlation and filtering the three kind of data. Then the spatial database of flue-cured tobacco planting based on Oracle can be further gained by been importing into the Oracle spatial database. Plenty of spatial data was stored in Oracle-based spatial database of tobacco planting and the amount of data kept increasing all the years. The speed of access must be influenced by the massive date amount when users query data. In order to solve this problem, some performance optimization methods based on Oracle Spatial Database of tobacco planting were proposed in this research.(1) The Oracle Clusterware method. With the purpose of improving the availability of data and reducing access latency, the system was improved into cluster environment from single-instance environment in this method.(2) The adjusting Oracle database memory method. In environment of Oracle RAC, the Oracle database memory was optimized by means of adjusting the size of SGA, automatic managing SGA, adjusting the size of the log buffer pool, recycle pool and keep pool to improve the efficiency of data access.(3) The partition table method. The amount of data in the tobacco planting spatial database based on Oracle is so large that usually the data stored in a table reached more than2G Under the Oracle rac environment, it will take a very long time to scan the entire table when users access the data that stored in normal tables. However, under the Oracle rac environment, when the partition table was applied to store data, users just need to visit some partitions of the partition table to acquire the needed data. Thus the efficiency and time of data access can been improved a lot.(4) The materialized views method. In this method, the data which is accessed frequently by users is extracted into a view. Under the Oracle rac environment, when using the normal view on the partition table, the operation of querying view is needed for every visiting. Especially when come across the complex queries, the time will spend longer. So the efficiency of data accessing will be reduced. But, under the Oracle rac environment, if the materialized views that is on the partition table are used to store these frequently accessed data, users only need to query the materialized view which already contains these data instead of visiting the database. Thereby, to a large extent, the efficiency of data access can be improved.(5) The space operation method. Under the Oracle rac environment, space objects are stored in the partition table. The efficiency and time can also be largely improved if the spatial operators and spatial functions selected reasonably, when users process the space adjacent analysis.