In Oracle, the ‘select’ statement must have a ‘from’ clause. However, some queries don’t require any table. They just perform some operation or calculation based on some data that is irrelevant to the table. for example, SELECT UPPER(‘hello world’) from… Read More
maven relativePath
maven supports parent-child relationship, where the configuration of the parent project is inherited by the child project. This relationship is specified using the <parent> element as below: <parent> <groupId>com.mygroup</groupId> <artifactId>artifactId</artifactId> <version>1.1</version> </parent> The pom file of the parent project will… Read More
fix ‘could not connect to display’ issue
Today I tried to run foxit reader installer in my Ubuntu Linux as root account. I got the below error message: QXcbConnection: Could not connect to display After struggling for a while, I found the below solution that fix this… Read More