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How to check if a function exists on a SQL database
...s for this type argument, particularly:
FN : Scalar function
IF : Inline table-valued function
TF : Table-valued-function
FS : Assembly (CLR) scalar-function
FT : Assembly (CLR) table-valued function
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postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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Most Pythonic way to provide global configuration variables in config.py? [closed]
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"mysql": {
"user": "root",
"pass": "secret",
"tables": {
"users": "tb_users"
}
# etc
}
}
You'd access the values as follows:
config["mysql"]["tables"]["users"]
If you are willing to sacrifice the potential to compute expressions ins...
How can I get Express to output nicely formatted HTML?
...:
foo.jade
h1 MyTitle
p
a(class='button', href='/users/') show users
table
thead
tr
th Name
th Email
tbody
- var items = [{name:'Foo',email:'foo@bar'}, {name:'Bar',email:'bar@bar'}]
- each item in items
tr
td= item.name
td= item.email
now you...
SQLite string contains other string query
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Using LIKE:
SELECT *
FROM TABLE
WHERE column LIKE '%cats%' --case-insensitive
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SQL update query using joins
I have to update a field with a value which is returned by a join of 3 tables.
11 Answers
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Create an empty data.frame
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You could use read.table with an empty string for the input text as follows:
colClasses = c("Date", "character", "character")
col.names = c("Date", "File", "User")
df <- read.table(text = "",
colClasses = colClasses,
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SQL Server: Get data for only the past year
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This will have very bad performance on big tables, you query will loop over every record to evaluate the year value of the date, it would be better to use a date range
– Adriaan Davel
May 30 '12 at 15:43
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Check with jquery if div has overflowing elements
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Works for most cases but won't cover up scenario with CSS tables (display table-cell, table-rwo, table) -
– Dmitry
Jul 1 '14 at 13:55
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Row count with PDO
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$sql = "SELECT count(*) FROM `table` WHERE foo = ?";
$result = $con->prepare($sql);
$result->execute([$bar]);
$number_of_rows = $result->fetchColumn();
Not the most elegant way to do it, plus it involves an extra query.
PDO has PDOStatemen...