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FIA. Forest Inventory Analysis Plots in forests over the US Coordinates “fuzzed” at 1km Tree species and characteristics Resampled every decade FIA database: Downloadable by state CSV files or MS-Access “CN” for primary keys Includes complete database dictionary!. MS-Access.
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FIA • Forest Inventory Analysis • Plots in forests over the US • Coordinates “fuzzed” at 1km • Tree species and characteristics • Resampled every decade • FIA database: • Downloadable by state • CSV files or MS-Access • “CN” for primary keys • Includes complete database dictionary!
MS-Access • Part of MS-Office professional • Relational database • No concurrent access • No spatial extensions • Has some unique characteristics • Brackets on field names: [Field1] • “Easy to Use” wizards for queries • Can get to SQL statements behind the wizards
Adding Joins Drag to Join Tables
SQL View SELECT PLOT.[CN] FROM (PLOT INNER JOIN TREE ON PLOT.CN = TREE.PLT_CN) INNER JOIN REF_SPECIES ON TREE.SPCD = REF_SPECIES.SPCD;
MS-Access • Access uses “*” for a string wildcard • Fieldnames are in brackets (sometimes) • First “INNER JOIN” must be in parenthesis
Final Query SELECT PLOT.[CN], PLOT.LAT, PLOT.LON, REF_SPECIES.COMMON_NAME, TREE.HT FROM (PLOT INNER JOIN TREE ON PLOT.CN = TREE.PLT_CN) INNER JOIN REF_SPECIES ON TREE.SPCD = REF_SPECIES.SPCD WHERE (((REF_SPECIES.COMMON_NAME) Like 'Doug*') AND ((TREE.HT)>200)) ORDER BY TREE.HT DESC;