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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.
...
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.
...
The case against checked exceptions
...with it.
This would be clearer with a counter-case. Imagine I'm writing a table API. I have the table model somewhere with an API including this method:
public RowData getRowData(int row)
Now as an API programmer I know there will be cases where some client passes in a negative value for the ro...
What is lazy loading in Hibernate?
...e child when parent is loaded from the database.
Example :
If you have a TABLE ? EMPLOYEE mapped to Employee object and contains set of Address objects.
Parent Class : Employee class,
Child class : Address Class
public class Employee {
private Set address = new HashSet(); // contains set of ch...
PostgreSQL: How to make “case-insensitive” query
...indexes to no longer be seekable. If this is a large or frequently queried table, that could cause trouble. Case-insensitive collation, citext, or a function-based index will improve performance.
– Jordan
Aug 10 '11 at 4:23
...
How can I convert a std::string to int?
...: std::ctype<char>
{
numeric_only(): std::ctype<char>(get_table()) {}
static std::ctype_base::mask const* get_table()
{
static std::vector<std::ctype_base::mask>
rc(std::ctype<char>::table_size,std::ctype_base::space);
std::fill(&am...
How to change the type of a field?
...big deal no matter how you do it. If you were using SQL and this was a big table you would probably have to take some down time.
– Gates VP
Jun 28 '16 at 18:16
...