doc: Change table alias names to lower case in tutorial chapter
This is needlessly different from our usual style otherwise. Author: Jürgen Purtz <juergen@purtz.de> Discussion: https://www.postgresql.org/message-id/flat/158996922318.7035.10603922579567326239@wrigleys.postgresql.org
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@ -609,11 +609,11 @@ SELECT *
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following query:
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<programlisting>
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SELECT W1.city, W1.temp_lo AS low, W1.temp_hi AS high,
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W2.city, W2.temp_lo AS low, W2.temp_hi AS high
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FROM weather W1, weather W2
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WHERE W1.temp_lo < W2.temp_lo
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AND W1.temp_hi > W2.temp_hi;
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SELECT w1.city, w1.temp_lo AS low, w1.temp_hi AS high,
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w2.city, w2.temp_lo AS low, w2.temp_hi AS high
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FROM weather w1, weather w2
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WHERE w1.temp_lo < w2.temp_lo
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AND w1.temp_hi > w2.temp_hi;
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</programlisting>
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<screen>
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@ -624,8 +624,8 @@ SELECT W1.city, W1.temp_lo AS low, W1.temp_hi AS high,
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(2 rows)
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</screen>
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Here we have relabeled the weather table as <literal>W1</literal> and
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<literal>W2</literal> to be able to distinguish the left and right side
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Here we have relabeled the weather table as <literal>w1</literal> and
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<literal>w2</literal> to be able to distinguish the left and right side
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of the join. You can also use these kinds of aliases in other
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queries to save some typing, e.g.:
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<programlisting>
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@ -126,13 +126,13 @@ SELECT *
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FROM weather LEFT OUTER JOIN cities ON (weather.city = cities.name);
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-- Suppose we want to find all the records that are in the temperature range
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-- of other records. W1 and W2 are aliases for weather.
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-- of other records. w1 and w2 are aliases for weather.
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SELECT W1.city, W1.temp_lo, W1.temp_hi,
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W2.city, W2.temp_lo, W2.temp_hi
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FROM weather W1, weather W2
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WHERE W1.temp_lo < W2.temp_lo
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and W1.temp_hi > W2.temp_hi;
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SELECT w1.city, w1.temp_lo, w1.temp_hi,
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w2.city, w2.temp_lo, w2.temp_hi
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FROM weather w1, weather w2
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WHERE w1.temp_lo < w2.temp_lo
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and w1.temp_hi > w2.temp_hi;
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-----------------------------
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