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How can I pass a member function where a free function is expected?

...)(void*, int, int), void* context) { fptr(context, 17, 42); } void non_member(void*, int i0, int i1) { std::cout << "I don't need any context! i0=" << i0 << " i1=" << i1 << "\n"; } struct foo { void member(int i0, int i1) { std::cout << "memb...
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Insert, on duplicate update in PostgreSQL?

...FLICT clause. with the following syntax (similar to MySQL) INSERT INTO the_table (id, column_1, column_2) VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z') ON CONFLICT (id) DO UPDATE SET column_1 = excluded.column_1, column_2 = excluded.column_2; Searching postgresql's email group a...
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Add list to set?

...rticle. Pythons hashing algorithms are explained on effbot.org and pythons __hash__ function in the python reference. Some facts: Set elements as well as dictionary keys have to be hashable Some unhashable datatypes: list: use tuple instead set: use frozenset instead dict: has no official count...
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Is it possible to GROUP BY multiple columns using MySQL?

...y the rows are sorted. In your example, you would write GROUP BY fV.tier_id, f.form_template_id Meanwhile, the code GROUP BY f.form_template_id, fV.tier_id would give similar results, but sorted differently. share ...
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Safely remove migration In Laravel

...teps: Manually delete the migration file under app/database/migrations/my_migration_file_name.php Reset the composer autoload files: composer dump-autoload Relax If you did run the migration (php artisan migrate), you may do this: a) Run migrate:rollback - it is the right way to undo the last...
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Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]

...tabase tables (instead of "dbo"). More importantly it will also prefix the __MigrationHistory table(s), e.g. Customer.__MigrationHistory. So you can have more than one __MigrationHistory table in a single database, one for each context. So the changes you make for one context will not mess with the ...
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数据结构与本地数据库 08:导出、备份与独立完成卡片库 · App Inventor 2 中文网

... 实例名 组件 本课配置 标签_标题 标签 Width=Fill parent;FontSize=24;TextColor=#183153;Text=知识卡片 · 第 8课 微数据库1 微数据库 Namespace=CardsB08 按钮_导出CSV ...
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What are valid values for the id attribute in HTML?

...wed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods ("."). HTML 5 is even more permissive, saying only that an id must contain at least one character and may not contain any space characters. The id attribute is case sensitive in XHTML. As a ...
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How To Change DataType of a DataColumn in a DataTable?

...newType) { using (DataColumn dc = new DataColumn(columnName + "_new", newType)) { // Add the new column which has the new type, and move it to the ordinal of the old column int ordinal = dt.Columns[columnName].Ordinal; dt.Columns.Add(dc); ...
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Where do I set my company name?

... If you want change __MyCompanyName__ in Xcode 4, you can try the following command. defaults write com.apple.dt.Xcode PBXCustomTemplateMacroDefinitions '{ORGANIZATIONNAME="YourNameHere";}' Carefully, this writes in the domain, com.apple.dt.Xc...