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How can I export the schema of a database in PostgreSQL?
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DataContractSerializer doesn't call my constructor?
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edited Feb 14 '14 at 10:08
Carsten
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Loading existing .html file with android WebView
...ew.loadUrl("file:///android_res/raw/myfile.html"); works only on API level 8. But it doesn't matter now.
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Unresolved specs during Gem::Specification.reset:
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edited Oct 17 '17 at 3:58
EricC
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How can I determine whether a Java class is abstract by reflection
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sethseth
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How to find corresponding log files folder for a web site?
...red Mar 19 '12 at 7:17
user626528user626528
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Find difference between timestamps in seconds in PostgreSQL
I have a table in PostgreSQL 8.3 with 2 timestamp columns. I would like to get the difference between these timestamps in seconds. Could you please help me how to get this done?
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What does the “>” (greater-than sign) CSS selector mean?
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Numbering rows within groups in a data frame
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Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
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MySQL: Selecting multiple fields into multiple variables in a stored procedure
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edited Feb 8 '15 at 17:50
answered Mar 15 '10 at 22:52
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