Examlex
When EXISTS or NOT EXISTS is used in a subquery, the select list of the subquery will usually just select all columns as a placeholder because it doesn't matter which columns are returned.
Q15: In the _ approach, one consolidated record
Q17: _ is an important scripting language to
Q47: Which of the following statements is true
Q69: Data in HDFS files cannot be updated.
Q75: A data expeditor is a person assigned
Q83: Relational databases are heavily based on the
Q85: All of the following are newer XML
Q85: The coding or scrambling of data so
Q101: Sample data are useful for developing prototype
Q102: What are the three different degrees of