You can change the data type of any column if all rows of the column contain nulls. However, if you change the data type of a column in a materialized view container table, then Oracle Database invalidates the corresponding materialized view.
US Economy. Definition: A stock market crash is when stock indexes lose more than 10% in a day or two. The broad indexes are the Dow Jones Industrial Average, the S&P 500, and the NASDAQ. The rapidity of the decline differentiates it from a stock market correction. That's a 10% loss over days, weeks or even months.
If you can put the word markets after it, I cover it. I started covering markets at Forbes in the summer of 2007. Right around then a pair of Bear Stearns hedge funds imploded in the first tremors of the financial crisis, but I swear the recession wasn't my fault.