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Multiple Indexes vs Multi-Column Indexes
I've just been adding an Index to a table in SQL Server 2005 and it got me thinking. What is the difference between creating 1 index and defining multiple columns over having 1 index per column you want to index.
...
How do I break a string over multiple lines?
... "this is my very very \"very\" long string, isn't it."
Summary
In this table, _ means space character. \n means "newline character" (\n in JavaScript), except for the "in-line newlines" row, where it means literally a backslash and an n).
> | " ' &...
The entity type is not part of the model for the current context
...g(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Estate>().ToTable("Estate");
}
If your tables are not created on startup, this is why. You need to tell the DbContext about them in the OnModelCreating method override.
You can either do custom per-entity mappings here, or separate t...
Original purpose of ? [closed]
...$_POST['delete_action'])) {
mysqli_query($connection, "DELETE FROM table_name
WHERE record_id = ".$_POST['row_to_be_deleted']);
//Here is where hidden field value is used
}
while(condition) {
?>
<span&g...
How to choose the id generation strategy when using JPA and Hibernate
...that are unique only when no other process is inserting data into the same table. Do not use in a cluster.
identity
supports identity columns in DB2, MySQL, MS SQL Server, Sybase and HypersonicSQL. The returned identifier is of type long, short or int.
sequence
uses a sequence in DB2, PostgreSQL, Or...
How does the const constructor actually work?
... time. They are canonicalized at compile time and stored in special lookup tables (where they are hashed by their canonical signatures) from which they are later reused.
P.S.
The form #Foo#int#1#int#1 used in these samples is only used for comparison purposes and it is not a real form of canonical...
How to escape single quotes in MySQL
...all) and it will still work.
Now, to load this into MySQL:
INSERT INTO my_table (text) VALUES (FROM_BASE64('
SWtGb0xDSWdUbVZoY214NUlFaGxZV1JzWlhOeklFNXBZMnNnZD
JGMlpXUWdZVzRnWld4bFoyRnVkQ0JvWVc1a0xDQWlZU0J0WVhS
MFpYCklnYjJZZ2JtOGdhVzF3YjNKMFlXNWpaUzRnTGlBdUlDNG
dTWFFuY3lCdWIzUWdZWE1nZEdodmRXZG9JRWt...
SQLite - replace part of a string
Is it possible using SQL in an SQLite table to replace part of a string?
3 Answers
...
Conditional formatting based on another cell's value
...zing feature is capable of, and especially how the $ thing works.
Example table
The color from D to G depend on the values in columns A, B and C. But the formula needs to check values that are fixed horizontally (user, start, end), and values that are fixed vertically (dates in row 1). That's wh...
How to use count and group by at the same select statement
...atement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
...