The company beat on the bottom line, but whiffed on revenue in its latest-reported quarter.Despite a mixed first quarter, investors gave the benefit of the doubt to Columbia Banking System (COLB 0.58%) on Friday. The Washington state-based company, arguably best known as the operator of the region's Umpqua Bank, managed to lift several of its more important metrics during the period. Its share price inched up by 0.6%, a rate slightly outpaced by the S&P 500 index's 1% rise.A miss on revenue, but a solid bea ...