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SQLite - UPSERT *not* INSERT or REPLACE

... (id, role, name) VALUES ( 1, 'code monkey', (SELECT name FROM Employee WHERE id = 1) ); This will update 2 of the columns. When ID=1 exists, the ROLE will be unaffected. When ID=1 does not exist, the role will be set to 'Benchwarmer' instead of the default v...
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how to check the dtype of a column in python pandas

...know this is a bit of an old thread but with pandas 19.02, you can do: df.select_dtypes(include=['float64']).apply(your_function) df.select_dtypes(exclude=['string','object']).apply(your_other_function) http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.DataFrame.select_dtypes.h...
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What is the difference between JOIN and UNION?

...t -- completely different operations. Trivial example of UNION: mysql> SELECT 23 AS bah -> UNION -> SELECT 45 AS bah; +-----+ | bah | +-----+ | 23 | | 45 | +-----+ 2 rows in set (0.00 sec) similary trivial example of JOIN: mysql> SELECT * FROM -> (SELECT 23 AS bah...
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How do I spool to a CSV formatted file using SQLPLUS?

...you want for numbers (avoid scientific notation on IDs) spool myfile.csv select table_name, tablespace_name from all_tables where owner = 'SYS' and tablespace_name is not null; Output will be like: TABLE_PRIVILEGE_MAP ,SYSTEM SYSTEM_PRIVILEGE_MAP...
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How to select rows that have current day's timestamp?

I am trying to select only today's records from a database table. 9 Answers 9 ...
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PreparedStatement IN clause alternatives?

... and cons of each is available here. The suggested options are: Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful. Prepare SELECT my_column FROM my_table WHERE search_...
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How to get a list of user accounts using the command line in MySQL?

... Use this query: SELECT User FROM mysql.user; Which will output a table like this: +-------+ | User | +-------+ | root | +-------+ | user2 | +-------+ As Matthew Scharley points out in the comments on this answer, you can group by the ...
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Selecting/excluding sets of columns in pandas [duplicate]

...e to create views or dataframes from an existing dataframe based on column selections. 9 Answers ...
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How to detect when cancel is clicked on file input?

...s not exposed to the browser." This is not true if the dialog is closed by selecting a file. – Trevor Dec 1 '16 at 22:24 ...
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Selecting only first-level elements in jquery

How can I select the link elements of only the parent <ul> from a list like this? 10 Answers ...