大约有 24,000 项符合查询结果(耗时:0.0506秒) [XML]

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Dump a mysql database to a plaintext (CSV) backup from the command line

... In MySQL itself, you can specify CSV output like: SELECT order_id,product_name,qty FROM orders INTO OUTFILE '/tmp/orders.csv' FIELDS TERMINATED BY ',' ENCLOSED BY '"' LINES TERMINATED BY '\n' From http://www.tech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-fil...
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Javascript equivalent of Python's zip function

...date: Here's a snazzier Ecmascript 6 version: zip= rows=>rows[0].map((_,c)=>rows.map(row=>row[c])) Illustration equiv. to Python{zip(*args)}: > zip([['row0col0', 'row0col1', 'row0col2'], ['row1col0', 'row1col1', 'row1col2']]); [["row0col0","row1col0"], ["row0col1","row1col1"...
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add column to mysql table if it does not exist

... Note that INFORMATION_SCHEMA isn't supported in MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good. One solution used by frameworks that use database migrations is...
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Socket.IO - how do I get a list of connected sockets/clients?

...lients('room'); anymore. Instead you can use the following var clients_in_the_room = io.sockets.adapter.rooms[roomId]; for (var clientId in clients_in_the_room ) { console.log('client: %s', clientId); //Seeing is believing var client_socket = io.sockets.connected[clientId];//Do whatever y...
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How can I hash a password in Java?

...m recommended cost, used by default */ public static final int DEFAULT_COST = 16; private static final String ALGORITHM = "PBKDF2WithHmacSHA1"; private static final int SIZE = 128; private static final Pattern layout = Pattern.compile("\\$31\\$(\\d\\d?)\\$(.{43})"); private final Se...
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Iterate a list as pair (current, next) in Python

... Since the_list[1:] actually creates a copy of the whole list (excluding its first element), and zip() creates a list of tuples immediately when called, in total three copies of your list are created. If your list is very large, you ...
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How do you test that a Python function throws an exception?

...t ahold of the actual Exception object thrown: import unittest def broken_function(): raise Exception('This is broken') class MyTestCase(unittest.TestCase): def test(self): with self.assertRaises(Exception) as context: broken_function() self.assertTrue('This i...
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How to find/remove unused dependencies in Gradle

...nsitive dependencies that are used directly by your code to explicit first order dependencies. Relocates dependencies to the 'correct' configuration. To apply the rule, add: gradleLint.rules += 'unused-dependency' Details of Unused Dependency Rule is given in the last part. To apply the Gradle...
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This IP, site or mobile application is not authorized to use this API key

... the new "project" must now be linked to a Google cloud billing account in order for the Google API to stop giving these various generic errors. Threshold can be set to $0 so you'll never be charged if usage exceeds the allowed quota. – Sparky Jul 16 '19 at 14...
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What is the single most influential book every programmer should read? [closed]

... For Computer Scientists http://ecx.images-amazon.com/images/I/51HCJ5R42KL._SL500_BO2,204,203,200_AA219_PIsitb-sticker-dp-arrow,TopRight,-24,-23_SH20_OU02_.jpg Discrete Mathematics For Computer Scientists by J.K. Truss. While this doesn't teach you programming, it teaches you fundamental mathemati...