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MySQL - Make an existing Field Unique
I have an already existing table with a field that should be unique but is not. I only know this because an entry was made into the table that had the same value as another, already existing, entry and this caused problems.
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Ship an application with a database
...re database from there. This is much quicker if the database has a lot of tables and other components. Upgrades are triggered by changing the database version number in the res/values/strings.xml file. Upgrades would then be accomplished by creating a new database externally, replacing the old dat...
MySQL Multiple Joins in one query?
...ally works? Is the second join joining the results of the first join with table 3, or is it joining table 1 with table 3 separately? (i.e., joining table 1 with table 2, and then joining table 1 separately with table 3, then returning it all back?) Does that make sense? I ask because I've been do...
Rails migration: t.references with alternative name?
So I have a create_table like this for Courses at a School:
5 Answers
5
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How do I create some kind of table of content in GitHub wiki?
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It is nicely demonstrated in the Table of Contents of the Markdown Cheatsheet.
##### Table of Contents
[Headers](#headers)
[Emphasis](#emphasis)
...snip...
<a name="headers"/>
## Headers
If you hover over a Header in a GitHub Markdown file...
Having both a Created and Last Updated timestamp columns in MySQL 4.0
I have the following table schema;
11 Answers
11
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How to delete all the rows in a table using Eloquent?
... for Laravel 4 and 5:
MyModel::truncate();
That drops all rows from the table without logging individual row deletions.
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Add table row in jQuery
What is the best method in jQuery to add an additional row to a table as the last row?
39 Answers
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Insert, on duplicate update in PostgreSQL?
...LICT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group ar...
Importing a CSV file into a sqlite3 database table using Python
...nge to 'sqlite:///your_filename.db'
cur = con.cursor()
cur.execute("CREATE TABLE t (col1, col2);") # use your column names here
with open('data.csv','r') as fin: # `with` statement available in 2.5+
# csv.DictReader uses first line in file for column headings by default
dr = csv.DictReader(...