A stock market data error that occurred on Jul 02, 2017 set an undetermined number of companies listed on the US Nasdaq exchange to a share price of $123.47, sending some tech companies’ stock prices crashing and others’ soaring.
In a statement from Nasdaq said the culprit was “improper use of test data” that was picked up by third party financial data providers. The exchange said it was “working with third party vendors to resolve this matter.”
Improper use of test data could likely be:
1. a hard-coded value or parameters
2. a hard-coded business logic in the program
3. a hard-coded debugging logic set by the program developer
4. a test data or dummy data inserted manually by the developer into the production database. This act bypassed the expected data validation and doesn't ensure data integrity.
So to all Pasti Nyala developers, take note of the following:
1. avoid hard-coded values unless it is a preset lower limit or upper limit
2. debugging logic is meant for use during testing stage
3. above all, avoid back-door data manipulation (e.g using DB tools to insert rows, or update rows). Data must be created or maintained by a tested program.