透明图层
When exploring data or laying out maps, setting some layers to be partially transparent can help you to view your data in the context of other data, including the basemap
数据集
Viewing the attached metadata is the best first step to learn more about a dataset.
符号
Symbology is a property of layers loaded into ArcMap, so it is set directly on the layer
Scale dependent rendering
Scale dependent rendering allows the user control over what layers are displayed at which scale. This allows the user flexible control over what they see.current map scale.
Normally it is useful to hide small items when zoomed out to keep the display uncluttered.为整洁，缩小时隐藏小内容
属性
Each record in an attribute table for a feature class has a feature associated with it and each feature has a record.属性表
select by attributes tool
query
like
‘ABC%‘: 所有以 ‘ABC‘ 起头的字串