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Create Pandas DataFrame from a string
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FYI - pd.read_table() is an equivalent function, just slightly better nomenclature: df = pd.read_table(TESTDATA, sep=";").
– wkzhu
Dec 6 '17 at 23:17
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UPDATE and REPLACE part of a string
I've got a table with two columns, ID and Value . I want to change a part of some strings in the second column.
9 Answer...
Changing column names of a data frame
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Try setnames() in the data.table package. Use something like setnames(DT,"b","B") or setnames(DT,c("a","E"),c("A","F"))
– dwstu
Aug 11 '14 at 17:23
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SQLite select where empty?
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It looks like you can simply do:
SELECT * FROM your_table WHERE some_column IS NULL OR some_column = '';
Test case:
CREATE TABLE your_table (id int, some_column varchar(10));
INSERT INTO your_table VALUES (1, NULL);
INSERT INTO your_table VALUES (2, '');
INSERT INTO your_t...
Set a DateTime database field to “Now”
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In SQL you need to use GETDATE():
UPDATE table SET date = GETDATE();
There is no NOW() function.
To answer your question:
In a large table, since the function is evaluated for each row, you will end up getting different values for the updated field.
So, if yo...
Datatables - Search Box outside datatable
I'm using DataTables ( datatables.net ) and I would like my search box to be outside of the table (for example in my header div).
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Error 1046 No database Selected, how to resolve?
...ell MySQL which database to use:
USE database_name;
before you create a table.
In case the database does not exist, you need to create it as:
CREATE DATABASE database_name;
followed by:
USE database_name;
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
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Suppose I have the following table T:
a b
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1 abc
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But wha...
How do I clone a Django model instance object and save it to the database?
...tion checking and depending on if they pass, i.e. the object is in another table that you are checking, you can set the new_instance.id = original_instance.id and save :) Thanks!
– radtek
Sep 25 '14 at 21:43
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How to create ENUM type in SQLite?
I need to convert a table from MySQL to SQLite, but I can't figure out how to convert an enum field, because I can't find ENUM type in SQLite.
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