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You can test for that sleet condition or a snow depth greater than 0, as shown here: SELECT * FROM station_data WHERE rain = 1 AND temperature <= 32 OR snow_depth > 0; But there is one possible problem here. While this technically works, there is a degree of ambiguity that we were lucky SQLite interpreted correctly. ” The SQL interpreter could derail quickly and incorrectly interpret that we are looking for rain AND another condition where either the temperature is below 32 OR the snow depth is greater than 0.

Note that some platforms, including Oracle, do not support aliases in the HAVING statement (just like the GROUP BY). This means you must specify the aggregate func‐ tion again in the HAVING statement. If you were running the preceding query on an Oracle database, you would have to write it like this: SELECT year, SUM(precipitation) as total_precipitation FROM station_data GROUP BY year HAVING SUM(precipitation) > 30 The HAVING Statement | 45 Getting Distinct Records It is not uncommon to want a set of distinct results from a query.

So the first part of the SQL shown here should be read as “Select all columns,” where * is a placeholder to specify all columns: SELECT * FROM CUSTOMER; And you are getting these columns from the CUSTOMER table: SELECT * FROM CUSTOMER; When you execute this SELECT statement, it brings back all the columns from the CUSTOMER table and displays them to you (Figure 4-3). Retrieving Data with SQL | 21 Figure 4-3. Selecting all records from the CUSTOMER table You do not have to pull all columns in a SELECT statement.

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ACTUALTESTS Oracle 1Z0-007 Exam Q and A 04 04 05


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