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How to log PostgreSQL queries?
How to enable logging of all SQL executed by PostgreSQL 8.3?
10 Answers
10
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Most efficient conversion of ResultSet to JSON?
... with the reading. I think Oracle cursor are server side by default. For MySQL > 5.0.2 look for useCursorFetch at connection url paramenter. Check about your favourite DBMS.
1: So to use less memory we must:
use server side cursor behind the scene
use resultset open as read only and, of course...
What is a 'multi-part identifier' and why can't it be bound?
...g all of the required columns in the target table.
Something like redgate sql prompt is brilliant for avoiding having to manually type these (it even auto-completes joins based on foreign keys), but isn't free. SQL server 2008 supports intellisense out of the box, although it isn't quite as comple...
Is there a way to auto-adjust Excel column widths with pandas.ExcelWriter?
...he headers instead. Hope this helps someone :)
import pandas as pd
import sqlalchemy as sa
import urllib
read_server = 'serverName'
read_database = 'databaseName'
read_params = urllib.quote_plus("DRIVER={SQL Server};SERVER="+read_server+";DATABASE="+read_database+";TRUSTED_CONNECTION=Yes")
read_...
Filter by property
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Nope. Django filters operate at the database level, generating SQL. To filter based on Python properties, you have to load the object into Python to evaluate the property--and at that point, you've already done all the work to load it.
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初窥InnoDB的Memcached插件 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...种原因，HandlerSocket并没有真正流行起来，不过庆幸的是MySQL官方受其启发，研发了基于InnoDB的Memcached插件，总算是在MySQL中延续了NoSQL的香火，以前单独架设Memcached服务器不仅浪费了内存，而且还必须自己维护数据的不一致问题...
What is the difference between map and flatMap and a good use case for each?
...ocessing the data.
Below is the sample data file.
hadoop is fast
hive is sql on hdfs
spark is superfast
spark is awesome
The above file will be parsed using map and flatMap.
Using map
>>> wc = data.map(lambda line:line.split(" "));
>>> wc.collect()
[u'hadoop is fast', u'hive ...
What are OLTP and OLAP. What is the difference between them?
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"When in doubt, I just use SQL." - SQL is a language and this doesn't answer the question. There's all kinds of data mgmt systems that know how interpret SQL and to translate it for working with all kinds of datasources behind the hood. One can make sq...
PostgreSQL naming conventions
Where can I find a detailed manual about PostgreSQL naming conventions? (table names vs. camel case, sequences, primary keys, constraints, indexes, etc...)
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SQL query to get all values a enum can have
Postgresql got enum support some time ago.
4 Answers
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