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Set default value of an integer column SQLite
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It's the same logic used in MySQL; the default of a nullable column is already NULL, so to set a default otherwise would imply the column is non-nullable. If you specify a default on a nullable column without declaring it NOT NULL, it may confuse you wh...
Using an image caption in Markdown Jekyll
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That is a great idea! However, site_root is not accepted as a valid variable. When rendered it ends up as src="{{ site.url_root }}....
– orschiro
Oct 14 '13 at 19:48
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Strings as Primary Keys in SQL Database [closed]
...Good explanation. But holds this true for all SQL databases? I've heard of MySQL performance issues when using random UUID as primary key.
– hgoebl
Aug 27 '17 at 11:08
add a c...
Excel to CSV with UTF8 encoding [closed]
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Needed to export an XLS as CSV to import in MySQL. Using Excel 2003 I exported in format "Unicode Text (.txt)", then used Notepad++ to replace the TAB with ;, then imported the txt-file into phpmyadmin with default "Character set of the file: utf-8", Format "CSV using ...
Why should I use document based database instead of relational database?
... my schema, I am constantly frustrated by having to maintain the schema in MySQL/SQLite. While I've not done too much with CouchDB yet, I do like how simple it is to evolve the schema during the RAD process.
A case where you might not want to use a non-relational database is when you have a lot of ...
Renaming columns in pandas
...rename(columns=lambda x: x.lstrip(), inplace=True)
– root-11
Oct 21 '13 at 22:05
2
Similar to @ro...
Memcached vs. Redis? [closed]
...us commands like popping/reading a random item and commands for performing unions and intersections with other sets.
Sorted Sets (commands)
Sorted Sets are also collections of unique values. These ones, as the name implies, are ordered. They are ordered by a score, then lexicographically.
This data ...
Issue with adding common code as git submodule: “already exists in the index”
...s number of steps and this worked for me.
Assuming you are in the project root directory and sample git module name is "c3-pro-ios-framework"
Remove the files associated to the submodule
rm -rf .git/modules/c3-pro-ios-framework/
Remove any references to submodule in config
vim .git/config
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How to create a DialogFragment without title?
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@clocksmith is the android:layout_width attribute for the root view in the layout for your dialog set to wrap_content?
– ataulm
Dec 30 '14 at 4:07
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Computed / calculated / virtual / derived columns in PostgreSQL
...s defined in the SQL standard and implemented by some RDBMS including DB2, MySQL and Oracle. Nor the similar "computed columns" of SQL Server.
STORED generated columns are introduced with Postgres 12. Trivial example:
CREATE TABLE tbl (
int1 int
, int2 int
, product bigint GENERATED ALWAYS...