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Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
I'm running the following MySQL UPDATE statement:
17 Answers
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How to change the default charset of a MySQL table?
There is a MySQL table which has this definition taken from SQLYog Enterprise :
5 Answers
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Random record in ActiveRecord
... for 100 randomly selected entries. (Be aware that it's RANDOM() in PostgreSQL and RAND() in MySQL ... not as portable as you may want it to be.)
– Florian Pilz
Jun 16 '11 at 13:17
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Use LINQ to get items in one List, that are not in another List
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Bit late to the party but a good solution which is also Linq to SQL compatible is:
List<string> list1 = new List<string>() { "1", "2", "3" };
List<string> list2 = new List<string>() { "2", "4" };
List<string> inList1ButNotList2 = (from o in list1
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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
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PostgreSQL 9.0 or later:
Recent versions of Postgres (since late 2010) have the string_agg(expression, delimiter) function which will do exactly what the question asked for, even letting you specify the delimiter string:
SELECT co...
PostgreSQL Autoincrement
I'm switching from MySQL to PostgreSQL and was wondering how I can do autoincrement values. I saw in the PostgreSQL docs a datatype "serial", but I get syntax errors when using it (in v8.0).
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Quickly reading very large tables as dataframes
...ata is passed to and from R in a binary format, which is faster.) read.csv.sql in the sqldf package, as described in JD Long's answer, imports data into a temporary SQLite database and then reads it into R. See also: the RODBC package, and the reverse depends section of the DBI package page. MonetD...
Howto: Clean a mysql InnoDB storage engine?
Is it possible to clean a mysql innodb storage engine so it is not storing data from deleted tables?
2 Answers
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现实版《道士下山》：道长老梁的四面人生 - 轻松一刻 - 清泛网 - 专注C/C++...
...个真实自在的自己，开心快乐，坦然面对生活。”
即便包括父亲在内的家人，并不理解他选择出家，甚至还有异样的眼光，但“他知道我不是在做坏事害人，他就满意了”。
其实，老梁还有个目标远大的“理想”，希望有一...
Similarity String Comparison in Java
... Here's an article showing how combine Levenshtein with an efficient SQL query: literatejava.com/sql/fuzzy-string-search-sql
– Thomas W
Apr 26 '14 at 2:11
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