在11gr2之后,当一个表的块数大于_small_table_threshold的时候,就被判定为大表,否则就视为小表。对于大表,在进行全表扫描的时候,oracle会根据_serial_direct_read的值来确定是否执行direct path read,如果值为auto,那就会direct path read。 参考文章: http://www.eygle.com/archives/2012/05/oracle_...
从11g开始Oracle通过内部算法来决定串行扫描大表是通过直接路径读direct path read,还是先读入到buffer cache中,此算法依据表的大小评估。_small_table_threshold 隐藏参数指定了 ORACLE中大表的阀值,其单位为block,即大于_small_table_threshold 所指定的块数的表被视作大表,否之视为"small table"。 对于大表"larg...
在11g之前串行的扫描大表默认总是先将数据读取到Oracle高速缓冲中,其等待事件常为db file scattered read。从11g开始Oracle通过内部算法来决定串行扫描大表是通过直接路径读direct path read,还是先读入到buffer cache中,此算法依据表的大小评估。 本文转自maclean_007 51CTO博客,原文链接:http://blog.51cto.com/macle...
(these are data that are serial in time). If the data are serial in spatial terms they do not, however, carry direct (implicit or explicit) locational information.Spatial locationmay be inferred indirectly through an external index. Such an index may, for example, associate the sequence ...
在VEE Instrument Manager中的接口，您使用带有WRITE和READ事务的Direct I / O对象来发送和接收数据。当...
R. et al. Direct observation of ultrafast collective motions in CO myoglobin upon ligand dissociation. Science 350, 445–450 (2015). This was the first sub-picosecond time resolution SFX study, on carboxymyoglobin, showing both large-scale motions and coherent oscillations of side chains upon ...
This connects to the USB port of the host PC, with the programming module plugging direct into the target PCB. The six-way in-circuit serial programming (ICSP) connector, between the programmer module and the target board, must be designed into the application circuit. An in-line row of ...
Serial to Parallel & Parallel to Serial Conversion - ScienceDirect This chapter demonstrates two useful functions of converting serial to parallel data and parallel to serial data. This is an extremely common task in modern Field Programmable Gate Array (FPGA) interfaces. In this task, most communi...
Additionally, some links direct to products from our own brand, DIYables. ※ OUR MESSAGES We are AVAILABLE for HIRE. See how to hire us to build your project PREVIOUS NEXT DISCLOSURE ArduinoGetStarted.com is a participant in the Amazon Services LLC Associates Program, an affiliate ...