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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...
MySQLDump one INSERT statement for each data row
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Use:
mysqldump --extended-insert=FALSE
Be aware that multiple inserts will be slower than one big insert.
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What special characters must be escaped in regular expressions?
...lavors (BRE/ERE)
Includes awk, ed, egrep, emacs, GNUlib, grep, PHP (ereg), MySQL, Oracle, R, sed.PCRE support may be enabled in later versions or by using extensions
ERE/awk/egrep/emacs
Outside a character class: . ^ $ * + ? ( ) [ { } \ |
Inside a character class: ^ - [ ]
BRE/ed/grep...
SQL set values of one column equal to values of another column in the same table
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How to prevent Node.js from exiting while waiting for a callback?
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I did look at felixge/node-mysql library and didn't see a reference to the command client.connect in the API. Is this the actual call you're trying to make (not trying to be nitpicky here)? Regardless, IMHO you need to think more about how Javascript...
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 ...
Laravel orderBy on a relationship
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If you use mysql strict mode, which is default in Laravel 5.4 ,f.ex you'll receive SQLSTATE[42000]: Syntax error or access violation: 1140 Mixing of GROUP columns ...
– Sabine
Feb 18 '17 at 15:15
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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...
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 ...
SQLAlchemy: how to filter date field?
..., once it's DateTime or timestamp - it's usually finished with 00:00 (both MySQL & PostgreSQL do this). More generic solution is not to cast, but to set the date you are sending to it's .endOfDay() so you actually send 1988-01-17 23:59:59 to the database compare :)
– jave.w...