Module 13 (Introduction to SQL - Part 2).pdf
Module 13 (Introduction to SQL - Part 2).pdf
Module 13 (Introduction to SQL - Part 2).pdf
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The CROSS JOINHowever, when running a cross-tab analysis, wesharply limit the size of the resulting recordset by(1) only asking for the fields we really need for theanalysis,(2) using WHERE clauses (<strong>to</strong> restrict recordselection <strong>to</strong> only the items we really need), and(3) using a lot of aggregate functions (<strong>to</strong> computesummary values over many records). Aggregatefunctions greatly reduce the resulting recordcount.