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C++ templates that accept only certain types

...that the compiler allows these, and then declare a variable my_template<char> z; and verify that it doesn't. – j_random_hacker Nov 16 '17 at 16:20 ...
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How to set auto increment primary key in PostgreSQL?

...able(moobars,foobars) values('worldwide interblag','2012-05-02') Step 3, select * from your table: el@voyager$ psql -U pgadmin -d kurz_prod -c "select * from epictable" Step 4, interpret the output: mytable_key | moobars | foobars -------------+-----------------------+------...
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Select random lines from a file

...e point is you can keep some lines in memory with shuffle to do the random selection of what to output. Sort is going to sort the entire file, regardless of what your needs are. – Rubens Sep 25 '14 at 2:01 ...
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Filter data.frame rows by a logical condition

... To select rows according to one 'cell_type' (e.g. 'hesc'), use ==: expr[expr$cell_type == "hesc", ] To select rows according to two or more different 'cell_type', (e.g. either 'hesc' or 'bj fibroblast'), use %in%: expr[expr$...
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How do I delete a Discipline in EPF Composer 1.5?

... I understand what you are looking for can be done through Configurations (select OpenUP in your Library view) and published View definitions. See slide 83 and 84 of this PPT document. You should be able to take it from there. An Introduction to the Eclipse Process Framework. In case the link doe...
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Are nested transactions allowed in MySQL?

...Y) ENGINE=InnoDB; START TRANSACTION; INSERT INTO t_test VALUES (1); SELECT * FROM t_test; id --- 1 SAVEPOINT tran2; INSERT INTO t_test VALUES (2); SELECT * FROM t_test; id --- 1 2 ROLLBACK TO tran2; SELECT * FROM t_test; id --- 1 ROLLBACK; SELECT * FROM ...
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How I can I lazily read multiple JSON values from a file/stream in Python?

... end_pos = int(re.match('Extra data: line \d+ column \d+ .*\(char (\d+).*\)', e.args[0]).groups()[0]) json_str = f.read(end_pos) obj = json.loads(json_str) start_pos += end_pos yield obj...
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Can we write our own iterator in Java?

If I have a list containing [alice, bob, abigail, charlie] and I want to write an iterator such that it iterates over elements that begin with 'a', can I write my own ? How can I do that ? ...
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Why am I getting “Cannot Connect to Server - A network-related or instance-specific error”?

...ation Click on Surface Area Configuration for Services and Connections Select the instance that is having a problem > Database Engine > Remote Connections Enable local and remote connections Restart instance You may need to create an exception on the firewall for the SQL Server ...
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Two single-column indexes vs one two-column index in MySQL?

... the statement I provided. Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries. share | improve this answer | ...