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Chapter 17 edits

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anthonydb 2021-09-02 17:08:11 -04:00
parent b89e5b9e19
commit a4bb6851b2
1 changed files with 4 additions and 6 deletions
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10
Chapter_17/Chapter_17.sql
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@ -138,11 +138,9 @@ percent_change(new_value numeric,
old_value numeric, old_value numeric,
decimal_places integer DEFAULT 1) decimal_places integer DEFAULT 1)
RETURNS numeric AS RETURNS numeric AS
$$ 'SELECT round(
SELECT round( ((new_value - old_value) / old_value) * 100, decimal_places
((new_value - old_value) / old_value) * 100, decimal_places );'
);
$$
LANGUAGE SQL LANGUAGE SQL
IMMUTABLE IMMUTABLE
RETURNS NULL ON NULL INPUT; RETURNS NULL ON NULL INPUT;
@ -151,7 +149,7 @@ RETURNS NULL ON NULL INPUT;
SELECT percent_change(110, 108, 2); SELECT percent_change(110, 108, 2);
-- Listing 17-13: Testing percent_change() on Census data -- Listing 17-13: Testing percent_change() on census data
SELECT c2019.county_name, SELECT c2019.county_name,
c2019.state_name, c2019.state_name,