An “unconventional measure of blowing off steam before the exam has prevailed in recent years, with students tearing their textbooks into pieces and throwing them off the school building. Some choose to yell in the school buildings to cheer themselves up as well.” The exams have been criticised for leading to a culture of cramming… Continue reading Chinese city bans students from tearing up textbooks, state media says
DB: Oracle 188.8.131.52.8 RAC OS: Solaris SPARC 10u11 Q: Parameter sec_case_sensitive_logon is set to default true. However, user still can logon with case insensitive words. i.e. both conn cfets261/cfets261 and cfets261/CFETS261 will succeed. The parameter seems not be working. A: The user data was imported from a 10g database, in which the password was stored… Continue reading sec_case_sensitive_logon seems not working
Business Requirement We have user tables which is used to store user and privilege information. Column AMM_FNCTY_BIT_STREAM is RAW(1025) and the BITS in the first 1024 bytes ( namely 8192 bits) represents 8192 different privilege flags. Now we need to decode the privilege column into different rows. In other words, if the bit flag in… Continue reading Rewriting SP to CTAS to improve performance
Ten-man Barcelona completed the Spanish league and cup double as two golas in extra time clinched the Copa del Rey. Luis Enrique’s side claimed the trophy for the 28th time despite having Javier Mascherano sent off in the first half. Suarez pulled the hamstring and was forced off. But Barca still held their own despite Sevilla… Continue reading Congratulations to Barcelona!
Q: If the database registers to IP1 and the listener listens on both IP1 and IP2. Will the client be able to connect to the database via IP2? A: Yes. Test environment: OS: Redhat Linux 6.3 x86_64 DB: Oracle 184.108.40.206 RAC [grid@bcmsdbs01 admin]$ lsnrctl status LISTENER_TEST LSNRCTL for Linux: Version 220.127.116.11.0 – Production on 13-MAY-2016… Continue reading Different register and connection IP
Character devices Character special files or character devices provide unbuffered, direct access to the hardware device. They do not necessarily allow programs to read or write single characters at a time; that is up to the device in question. The character device for a hard disk, for example, will normally require that all reads and… Continue reading Direct IO, AIO and device file
Today I found two interesting questions, which may sound pretty easy but actually requires lots of expertise to answer. Q1 How to identify which process is consuming swap space in a linux host? Q2 Why SWAP shows significant usage in top while free returns 0 usage for swap? Let’s start our voyage of discovery now.… Continue reading Swap Usage in Linux Host