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41f862ba87
three functions which exercise the tablefunc API.
show_all_settings()
- returns the same information as SHOW ALL, but as a query result
normal_rand(int numvals, float8 mean, float8 stddev, int seed)
- returns a set of normally distributed float8 values
- This routine implements Algorithm P (Polar method for normal
deviates) from Knuth's _The_Art_of_Computer_Programming_, Volume 2,
3rd ed., pages 122-126. Knuth cites his source as "The polar
method", G. E. P. Box, M. E. Muller, and G. Marsaglia,
_Annals_Math,_Stat._ 29 (1958), 610-611.
crosstabN(text sql)
- returns a set of row_name plus N category value columns
- crosstab2(), crosstab3(), and crosstab4() are defined for you,
but you can create additional crosstab functions per directions
in the README.
Joe Conway
48 lines
3.1 KiB
SQL
48 lines
3.1 KiB
SQL
--
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-- show_all_settings()
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--
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SELECT * FROM show_all_settings();
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--
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-- normal_rand()
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--
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SELECT * FROM normal_rand(100, 250, 5, EXTRACT(SECONDS FROM CURRENT_TIME(0))::int);
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--
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-- crosstab()
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--
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create table ct(id serial, rowclass text, rowid text, attribute text, value text);
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insert into ct(rowclass, rowid, attribute, value) values('group1','test1','att1','val1');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test1','att2','val2');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test1','att3','val3');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test1','att4','val4');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test2','att1','val5');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test2','att2','val6');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test2','att3','val7');
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insert into ct(rowclass, rowid, attribute, value) values('group1','test2','att4','val8');
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insert into ct(rowclass, rowid, attribute, value) values('group2','test3','att1','val1');
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insert into ct(rowclass, rowid, attribute, value) values('group2','test3','att2','val2');
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insert into ct(rowclass, rowid, attribute, value) values('group2','test3','att3','val3');
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insert into ct(rowclass, rowid, attribute, value) values('group2','test4','att1','val4');
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insert into ct(rowclass, rowid, attribute, value) values('group2','test4','att2','val5');
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insert into ct(rowclass, rowid, attribute, value) values('group2','test4','att3','val6');
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select * from crosstab2('select rowid, attribute, value from ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') order by 1,2;');
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select * from crosstab3('select rowid, attribute, value from ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') order by 1,2;');
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select * from crosstab4('select rowid, attribute, value from ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') order by 1,2;');
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select * from crosstab2('select rowid, attribute, value from ct where rowclass = ''group1'' order by 1,2;');
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select * from crosstab3('select rowid, attribute, value from ct where rowclass = ''group1'' order by 1,2;');
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select * from crosstab4('select rowid, attribute, value from ct where rowclass = ''group1'' order by 1,2;');
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select * from crosstab2('select rowid, attribute, value from ct where rowclass = ''group2'' and (attribute = ''att1'' or attribute = ''att2'') order by 1,2;');
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select * from crosstab3('select rowid, attribute, value from ct where rowclass = ''group2'' and (attribute = ''att1'' or attribute = ''att2'') order by 1,2;');
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select * from crosstab4('select rowid, attribute, value from ct where rowclass = ''group2'' and (attribute = ''att1'' or attribute = ''att2'') order by 1,2;');
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select * from crosstab2('select rowid, attribute, value from ct where rowclass = ''group2'' order by 1,2;');
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select * from crosstab3('select rowid, attribute, value from ct where rowclass = ''group2'' order by 1,2;');
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select * from crosstab4('select rowid, attribute, value from ct where rowclass = ''group2'' order by 1,2;');
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