An anonymous reader writes: Oracle is buying hospitality and retail technology vendor Micros Systems for $5.3 billion, in a deal that will be its largest since the purchase of Sun Microsystems in 2010. "Oracle said the acquisition will extend its offerings by combining Micros' industry-specific applications with its business applications, technologies and cloud portfolio. Oracle expects the deal to immediately add to its adjusted earnings. Its stock climbed 18 cents to $41 before the market opened. Micros' board unanimously approved the transaction, which is expected to close in the second half of the year."