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How can I view live MySQL queries?

...ry query run results in the query being inserted into some sort of history table, and then create a separate page to access this information. Do be aware that this will probably considerably slow down everything on the server though, with adding an extra INSERT on top of every single query. Edit...
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Have bash script answer interactive prompts [duplicate]

...[yes]` `#Skip plural name checking [no]` `#Use logged storage [no]` `#Sort tables and views [yes]` `#Export only table categorized []` `#Enhance many to many detection [yes]` `#Skip many to many tables [yes]` `#Bundle namespace []` `#Entity namespace []` `#Repository namespace []` `#Use automatic re...
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How do you use script variables in psql?

...nd can then be substituted, for example, as ... SELECT * FROM :myvariable.table1; ... or ... SELECT * FROM table1 WHERE :myvariable IS NULL; edit: As of psql 9.1, variables can be expanded in quotes as in: \set myvariable value SELECT * FROM table1 WHERE column1 = :'myvariable'; In olde...
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MYSQL Dump only certain rows

...t dumps everything. How can I get mysqldump to only dump certain rows of a table? 3 Answers ...
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What is the difference between UNION and UNION ALL?

...cted columns need to be of the same data type. Example: If we have two tables, 1) Employee and 2) Customer Employee table data: Customer table data: UNION Example (It removes all duplicate records): UNION ALL Example (It just concatenate records, not eliminate duplicates, so it...
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log4j logging hierarchy order

... This table might be helpful for you: Going down the first column, you will see how the log works in each level. i.e for WARN, (FATAL, ERROR and WARN) will be visible. For OFF, nothing will be visible. ...
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HashSet versus Dictionary w.r.t searching time to find if an item exists

... I assume you mean Dictionary<TKey, TValue> in the second case? HashTable is a non-generic class. You should choose the right collection for the job based on your actual requirements. Do you actually want to map each key to a value? If so, use Dictionary<,>. If you only care about it a...
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MySQL Query to select data from last week?

Hi I have a table with a date field and some other information. I want to select all entries from the past week, (week start from Sunday). ...
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How do I get current date/time on the Windows command line in a suitable format for usage in a file/

...en WMIC Path Win32_LocalTime Get Day,Hour,Minute,Month,Second,Year /Format:table. Likewise, to get 20120623-1619 in my local Amsterdam time zone, in one line: for /f %%a in ('wmic os get LocalDateTime ^| findstr ^[0-9]') do (set ts=%%a) & set datetime=%ts:~0,8%-%ts:~8,4% – ...
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Remove an entire column from a data.frame in R

... long amount of time and/or fail due to out of memory errors. Package data.table helps address this problem with the := operator: library(data.table) > dt <- data.table(a = 1, b = 1, c = 1) > dt[,a:=NULL] b c [1,] 1 1 I should put together a bigger example to show the differences. I...