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How to search a specific value in all tables (PostgreSQL)?
Is it possible to search every column of every table for a particular value in PostgreSQL?
8 Answers
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Numbering rows within groups in a data frame
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284
Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
l...
Assigning variables with dynamic names in Java
...<Integer> n = new ArrayList<Integer>();
for (int i = 1; i < 4; i++) {
n.add(5);
}
Map<String, Integer> n = new HashMap<String, Integer>();
for (int i = 1; i < 4; i++) {
n.put("n" + i, 5);
}
It is possible to use reflection to dynamically refer to variables ...
What's the best way to iterate over two or more containers simultaneously
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Konrad RudolphKonrad Rudolph
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Creating a new dictionary in Python
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edited Nov 8 '15 at 3:49
poolie
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answered Dec ...
MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
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edited Jun 11 '12 at 7:14
answered May 14 '09 at 5:51
Vin...
PHP ORMs: Doctrine vs. Propel
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answered Jan 14 '10 at 6:51
phidahphidah
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How to initialize static variables
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348
PHP can't parse non-trivial expressions in initializers.
I prefer to work around this by addin...
Can a program depend on a library during compilation but not runtime?
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edited Mar 22 '14 at 18:36
Emre Yazici
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AttributeError: 'module' object has no attribute 'urlopen'
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254
This works in Python 2.x.
For Python 3 look in the docs:
import urllib.request
with urllib.re...