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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
... to upgrade!
Building on Bill Karwin's answer, to spell out what a rule based approach would look like (transferring from another schema in the same DB, and with a multi-column primary key):
CREATE RULE "my_table_on_duplicate_ignore" AS ON INSERT TO "my_table"
WHERE EXISTS(SELECT 1 FROM my_tab...
Handling an empty UITableView. Print a friendly message
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Based on the answers here, here is a quick class I made that you can use on in your UITableViewController.
import Foundation
import UIKit
class TableViewHelper {
class func EmptyMessage(message:String, viewController:U...
Installing PDO driver on MySQL Linux server
...se PDO in order to parameterize my queries and safely save HTML in the database.
6 Answers
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Best way to test if a row exists in a MySQL table
... no difference to use *, 1 or NULL because EXISTS only tests for a boolean based on 1+ of the WHERE criteria matching.
– OMG Ponies
Nov 4 '09 at 23:28
78
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'pip' is not recognized as an internal or external command
...system settings>advanced>environment variables. I am using Windows 8 64bit. Thanks!
– Mohammed
Jan 4 '15 at 17:19
1
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instantiate a class from a variable in PHP?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How can I check which version of Angular I'm using?
...t something like this:
angular-cli: 1.0.0-beta.24
node: 7.4.0
os: darwin x64
@angular/common: 2.4.3
@angular/compiler: 2.4.3
@angular/core: 2.4.3
@angular/forms: 2.4.3
@angular/http: 2.4.3
@angular/platform-browser: 2.4.3
@angular/platform-browser-dynamic: 2.4.3
@angular/router: 3.4.3
@angular/comp...
Thread Safety in Python's dictionary
...ble. Much more costly will be the hours spent bug hunting in a complex codebase when those CPython implementation details change one day.
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Iterating over each line of ls -l output
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Convert Year/Month/Day to Day of Year in Python
...want to present performance of different approaches, on Python 3.4, Linux x64. Excerpt from line profiler:
Line # Hits Time Per Hit % Time Line Contents
==============================================================
(...)
823 1508 11334 ...