大约有 42,000 项符合查询结果(耗时:0.0425秒) [XML]

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How to get cumulative sum

... let put some data in the table** Insert Into CUMULATIVESUM Select 1, 10 union Select 2, 2 union Select 3, 6 union Select 4, 10 here I am joining same table (SELF Joining) Select c1.ID, c1.SomeValue, c2.SomeValue From CumulativeSum c1, CumulativeSum c2 Where c1.id >= c2.ID Order By c1.i...
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Reshaping data.frame from wide to long format

...f("Select Code, Country, '1950' As Year, `1950` As Value From wide Union All Select Code, Country, '1951' As Year, `1951` As Value From wide Union All Select Code, Country, '1952' As Year, `1952` As Value From wide Union All Select Code, Country, '1953' A...
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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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LINQ - Full Outer Join

.... The idea is to take a left outer join and right outer join then take the union of the results. var firstNames = new[] { new { ID = 1, Name = "John" }, new { ID = 2, Name = "Sue" }, }; var lastNames = new[] { new { ID = 1, Name = "Doe" }, new { ID = 3, Name = "Smith" }, }; var left...
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How do I calculate tables size in Oracle

... WHERE segment_type IN ('TABLE', 'TABLE PARTITION', 'TABLE SUBPARTITION') UNION ALL SELECT i.table_name, i.owner, s.bytes FROM dba_indexes i, dba_segments s WHERE s.segment_name = i.index_name AND s.owner = i.owner AND s.segment_type IN ('INDEX', 'INDEX PARTITION', 'INDEX SUBPARTITION') U...
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What are the use cases for selecting CHAR over VARCHAR in SQL?

...rchar, it's free to use 1-3 bytes per character as needed. This is in the MySQL manual: dev.mysql.com/doc/refman/5.0/en/charset-unicode-utf8.html – Gavin Towey Mar 27 '14 at 2:14 ...
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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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Hidden Features of MySQL

...QL Server with many years now but have only just recently started to use MySQL with my web applications, and I'm hungry for knowledge. ...
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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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linux下iptables配置详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术

...tables -Z -t nat 2,添加规则 添加基本的NAT地址转换,(关于如何配置NAT可以看我的另一篇文章), 添加规则,我们只添加DROP链.因为默认链全是ACCEPT. 防止外网用内网IP欺骗 [root@tp sysconfig]# iptables -t nat -A PREROUTING -i eth0 -s 10.0.0.0/8 -j DRO...