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Creating a simple XML file using python
...nt using the in-stdlib cElementTree:
import xml.etree.cElementTree as ET
root = ET.Element("root")
doc = ET.SubElement(root, "doc")
ET.SubElement(doc, "field1", name="blah").text = "some value1"
ET.SubElement(doc, "field2", name="asdfasd").text = "some vlaue2"
tree = ET.ElementTree(root)
tree.wr...
Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);...
Unknown column in 'field list' error on MySQL Update query
I keep getting MySQL error #1054, when trying to perform this update query:
11 Answers
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Select all columns except one in MySQL?
... trying to use a select statement to get all of the columns from a certain MySQL table except one. Is there a simple way to do this?
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What is the difference between MySQL Server and MySQL Client
...nstall both but what are the differences between the client and server for MySQL.
3 Answers
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In PHP with PDO, how to check the final SQL parametrized query? [duplicate]
In PHP, when accessing MySQL database with PDO with parametrized query, how can you check the final query (after having replaced all tokens)?
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How to reset AUTO_INCREMENT in MySQL?
...ccurs and the current sequence value is not changed.
See How to Reset an MySQL AutoIncrement using a MAX value from another table? on how to dynamically get an acceptable value.
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How do I check if a column is empty or null in MySQL?
...OR some_col = ' ' (one space inserted in the string) then it works on both MySQL and Oracle, see answer of "onedaywhen". some_col = '' doesn't work on Oracle as empty strings mean NULL there.
– Johanna
May 18 '15 at 14:07
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When should I use a composite index?
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@felwithe MySQL can only use one index per each of the tables in a query (Exemptions are there. eg, Merging of indexes). Which ideally means that a table in a query, must use a single index for all where-clause, table join, group-by an...
MySQL “between” clause not inclusive?
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From the MySQL-manual:
This is equivalent to the expression
(min <= expr AND expr <= max)
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