SQL execution order is indeed a critical aspect to understand for writing efficient queries, especially when dealing with complex operations involving filtering, grouping, and aggregation. Here's an explanation of the SQL execution order based on your outline:
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FROM: This clause specifies which table(s) or data source you are querying from.
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WHERE: Filters rows before any other operation is performed. Rows that do not satisfy this condition will be excluded from further processing.
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GROUP BY: Groups the filtered rows by one or more columns, preparing for aggregate functions to operate on these groups.
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HAVING: Filters out groups based on conditions after aggregation has been applied but before selecting final output. This is where you filter results of GROUP BY operations.
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SELECT: Specifies which columns should be included in the result set and allows computation of aggregates (e.g., SUM, AVG) over the grouped data.
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ORDER BY: Sorts the final result set based on specified columns or expressions. Sorting happens after all other clauses have been processed.
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LIMIT/OFFSET (if applicable): Limits the number of rows returned and allows skipping a certain number of initial rows, respectively.
Understanding this order is crucial for optimizing
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