Remove unused variable.
Remove unused variable.

zuowang/voltdb,kumarrus/voltdb,deerwalk/voltdb,simonzhangsm/voltdb,zuowang/voltdb,zuowang/voltdb,VoltDB/voltdb,migue/voltdb,flybird119/voltdb,paulmartel/voltdb,creative-quant/voltdb,ingted/voltdb,paulmartel/voltdb,kumarrus/voltdb,deerwalk/voltdb,simonzhangsm/voltdb,deerwalk/voltdb,paulmartel/voltdb,migue/voltdb,ingted/voltdb,simonzhangsm/voltdb,paulmartel/voltdb,flybird119/voltdb,kumarrus/voltdb,flybird119/voltdb,VoltDB/voltdb,creative-quant/voltdb,VoltDB/voltdb,zuowang/voltdb,deerwalk/voltdb,kumarrus/voltdb,migue/voltdb,creative-quant/voltdb,simonzhangsm/voltdb,flybird119/voltdb,paulmartel/voltdb,ingted/voltdb,paulmartel/voltdb,creative-quant/voltdb,simonzhangsm/voltdb,deerwalk/voltdb,zuowang/voltdb,VoltDB/voltdb,zuowang/voltdb,migue/voltdb,kumarrus/voltdb,ingted/voltdb,flybird119/voltdb,simonzhangsm/voltdb,migue/voltdb,VoltDB/voltdb,flybird119/voltdb,VoltDB/voltdb,flybird119/voltdb,zuowang/voltdb,ingted/voltdb,ingted/voltdb,zuowang/voltdb,migue/voltdb,deerwalk/voltdb,creative-quant/voltdb,paulmartel/voltdb,migue/voltdb,creative-quant/voltdb,ingted/voltdb,creative-quant/voltdb,migue/voltdb,paulmartel/voltdb,kumarrus/voltdb,deerwalk/voltdb,simonzhangsm/voltdb,creative-quant/voltdb,kumarrus/voltdb,flybird119/voltdb,simonzhangsm/voltdb,kumarrus/voltdb,VoltDB/voltdb,ingted/voltdb,deerwalk/voltdb