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SQL MAX of multiple columns?

...ate FROM ( SELECT d.date1 AS dDate UNION SELECT d.date2 UNION SELECT d.date3 ) a ) MaxDate , Cost FROM dates d GO Solution 3 (Simulated UNPIVOT) ;...
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What is the purpose of Order By 1 in SQL select statement?

...ted and working in SQL Server ;WITH cte AS( SELECT 1 AS Col1, 'z' AS Col2 UNION SELECT 2 AS Col1, 'y' AS Col2 UNION SELECT 3 AS Col1, 'x' AS Col2 ) SELECT Col2, Col1 FROM cte ORDER BY 1 – Ivanzinho Aug 27 '18 at 20:20 ...
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A better similarity ranking algorithm for variable length strings

...tr2.length-2).collect {|i| str2[i,2]}.reject { |pair| pair.include? " "} union = pairs1.size + pairs2.size intersection = 0 pairs1.each do |p1| 0.upto(pairs2.size-1) do |i| if p1 == pairs2[i] intersection += 1 pairs2.slice!(i) break end end end (2.0 * inter...
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LISTAGG in Oracle to return distinct values

...ta as ( select 'A' as col1, 'T_a1' as col2, '123' as col3 from dual union select 'A', 'T_a1', '456' from dual union select 'A', 'T_a1', '789' from dual union select 'A', 'T_a2', '123' from dual union select 'A', 'T_a2', '456' from dual union select 'A', 'T_a2', '111' from dual union select 'A...
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What does |= (ior) do in Python?

...ace+ operation between pairs of objects. In particular, between: sets: a union operation dicts: an update operation counters: a union (of multisets) operation numbers: a bitwise OR, binary operation In most cases, it is related to the | operator. See examples below. Sets For example, the union o...
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Counting null and non-null values in a single query

...a column... If that is correct: SELECT count(*) FROM us WHERE a IS NULL UNION ALL SELECT count(*) FROM us WHERE a IS NOT NULL Edited to have the full query, after reading the comments :] SELECT COUNT(*), 'null_tally' AS narrative FROM us WHERE a IS NULL UNION SELECT COUNT(*), 'not_null...
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How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?

...source INT) INSERT INTO @TestTable SELECT 1, 10, '2009-03-04', 'john', 399 UNION SELECT 2, 11, '2009-03-04', 'juliet', 244 UNION SELECT 5, 12, '2009-03-04', 'borat', 555 UNION SELECT 3, 10, '2009-03-03', 'john', 300 UNION SELECT 4, 11, '2009-03-03', 'juliet', 200 UNION SELECT 6, 12, '2009-03-03', 'b...
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Is having an 'OR' in an INNER JOIN condition a bad idea?

...LECT * FROM maintable m JOIN othertable o ON o.parentId = m.id UNION SELECT * FROM maintable m JOIN othertable o ON o.id = m.parentId , each of them being an equijoin, however, SQL Server's optimizer is not smart enough to see it in the query you wrote (though they are logi...
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SQL query return data from multiple tables

... Part 1 - Joins and Unions This answer covers: Part 1 Joining two or more tables using an inner join (See the wikipedia entry for additional info) How to use a union query Left and Right Outer Joins (this stackOverflow answer is excellent t...
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Is it possible to specify condition in Count()?

... [varchar](50) NOT NULL) INSERT INTO @tbl (id, field) SELECT 1, 'Manager' UNION SELECT 2, 'Manager' UNION SELECT 3, 'Customer' UNION SELECT 4, 'Boss' UNION SELECT 5, 'Intern' UNION SELECT 6, 'Customer' UNION SELECT 7, 'Customer' UNION SELECT 8, 'Wife' UNION SELECT 9, 'Son' SELECT * FROM @tbl SELE...