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rake db:schema:load vs. migrations
...n (very similar to your schema.rb file) and updating the schema_migrations table to reflect this change. Be very careful when doing this! You can easily delete your production data if you aren't careful.
As a side note, I strongly believe that you should never put data creation in the migration fil...
Find a pair of elements from an array whose sum equals a given number
...r=[1,2,1,2,1,2,1,...]. For uniqueness by value, it seems like another hash table keyed by a value-pair would do the trick. Still a nice, compact, elegant answer. +1
– William
Feb 10 '11 at 18:49
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Vertically align text within a div [duplicate]
...: 1px solid red;
height: 200px;
width: 100px;
}
div {
display: table-cell;
vertical-align:middle;
text-align: center;
}
It also works with <br /> in "yet another..."
share
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What exactly does Perl's “bless” do?
... });
console.log(animal.sound);
})();
The function takes a hash table of unordered properties(since it makes no sense to have to write properties in a specific order in dynamic languages in 2016) and returns a hash table with those properties, or if you forgot to put the new keyword, it w...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...tes you need to update characher-set and collation for utf8mb4:
database table/column:
alter table <some_table> convert to character set utf8mb4 collate utf8mb4_unicode_ci
database server connection (see)
On my development enviromnt for #2 I prefer to set parameters on command line when st...
Create PostgreSQL ROLE (user) if it doesn't exist
... and improved with @Gregory's comment.)
Unlike, for instance, with CREATE TABLE there is no IF NOT EXISTS clause for CREATE ROLE (up to at least pg 12). And you cannot execute dynamic DDL statements in plain SQL.
Your request to "avoid PL/pgSQL" is impossible except by using another PL. The DO sta...
Unable to generate an explicit migration in entity framework
...guration.
The solution was simply to update the ContextKey in the database table "__MigrationHistory" (or revert the value in the Configuration class I guess). The ContextKey and the Namespace in your application should match.
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How does Rails keep track of which migrations have run for a database?
...
Rails creates a table in your database called schema_migrations to keep track of which migrations have run.
The table contains a single column, version. When Rails runs a migration, it takes the leading digits in the migration's file name a...
Stretch background image css?
...t to cover the entire cell, then put the content on top of the image.
table {
width: 230px;
}
.style1 {
text-align: center;
height: 35px;
}
.bg {
position: relative;
width: 100%;
height: 100%;
}
.bg img {
display: block;
width: 100%;
height: 100%;
}
.b...
SQL Server database backup restore on lower version
...aurav Don't script out the data - instead, script out the entire database (tables, procs, triggers, constraints, etc) without data, create the new database, then right click the source database, go to "Tools", then "Export Data" to transfer the contents of the tables to your database.
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