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MySQL - UPDATE multiple rows with different values in one query
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Excuse my english sir, when i try to make an update mysql give me the error: # 1062 - Duplicate entry 'XXX' for key 'PRIMARY'. That does when I try to update a record with the same value it already had, is there any way to skip the update if the current value is the same as bein...
MySQL SELECT only not null values
...ERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
Edited to reflect comments. It sounds like your table may not be in first no...
How to turn off INFO logging in Spark?
...e it dynamically for your application using setLogLevel:
from pyspark.sql import SparkSession
spark = SparkSession.builder.\
master('local').\
appName('foo').\
getOrCreate()
spark.sparkContext.setLogLevel('WARN')
In the pyspark console, a default spark session ...
How do you write multiline strings in Go?
...nieleD That's a slight nonsequitur, but which dialect? Presumably mainly MySQL? stackoverflow.com/a/10574031 Note that by extension of the same argument, it's a pain for embedding markdown, or shell scripts (if you opt to use backtick in place of $(abcd)).
– Ivan Vučica
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Import multiple csv files into pandas and concatenate into one DataFrame
...p. as the Hapood ecosystem has growing list of tools where you can perform sql queries directly on many different directories containing different file types (csv, json, txt, databases) as if it was one data source. There must be something similar in python, since it has had a 20 year jump start ...
What underlies this JavaScript idiom: var self = this?
I saw the following in the source for WebKit HTML 5 SQL Storage Notes Demo :
10 Answers
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RESTful Authentication
...s available. For instance, in our framework, we cache the responses at the SQL level, not at the URI level. So adding this extra parameter doesn't break the cache mechanism.
See this article for some details about RESTful authentication in our client-server ORM/SOA/MVC framework, based on JSON and ...
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
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So, you have a
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
java.net.ConnectException: Connection refused
I'm quoting from this answer which also contains a step-by-step MySQL+JDBC tutorial:
If you ...
What's the fastest way to do a bulk insert into Postgres?
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PostgreSQL has a guide on how to best populate a database initially, and they suggest using the COPY command for bulk loading rows. The guide has some other good tips on how to speed up the process, like removing indexes and foreig...
Select Row number in postgres
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