let tableName = req.body.tableName
let colName = req.body.col1+","+req.body.col2
sqlString =INSERT INTO ${tableName}(${colName}) VALUES ($1,$2) RETURNING *
let tableName = req.body.tableName
let colName = req.body.col1+","+req.body.col2
sqlString =INSERT INTO ${tableName}(${colName}) VALUES ($1,$2) RETURNING *