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get list of pandas dataframe columns based on data type
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If you are just selecting columns by data type, then this answer is obsolete. Use select_dtypes instead
– Ted Petrou
Nov 3 '17 at 16:58
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Entity Framework select distinct name
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Using lambda expression..
var result = EFContext.TestAddresses.Select(m => m.Name).Distinct();
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Get records with max value for each group of grouped SQL results
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There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. T...
How can I get column names from a table in SQL Server?
... much more by querying the Information Schema views.
This sample query:
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'Customers'
Can be made over all these DB objects:
CHECK_CONSTRAINTS
COLUMN_DOMAIN_USAGE
COLUMN_PRIVILEGES
COLUMNS
CONSTRAINT_COLUMN_USAGE
CONSTRAINT_...
Formatting Numbers by padding with leading zeros in SQL Server
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Change the number 6 to whatever your total length needs to be:
SELECT REPLICATE('0',6-LEN(EmployeeId)) + EmployeeId
If the column is an INT, you can use RTRIM to implicitly convert it to a VARCHAR
SELECT REPLICATE('0',6-LEN(RTRIM(EmployeeId))) + RTRIM(EmployeeId)
And the code to re...
How to set variable from a SQL query?
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Using SELECT:
SELECT @ModelID = m.modelid
FROM MODELS m
WHERE m.areaid = 'South Coast'
Using SET:
SET @ModelID = (SELECT m.modelid
FROM MODELS m
WHERE m.areaid = 'South Coast')
See this...
Javascript Equivalent to C# LINQ Select
...always add custom methods to the array prototype as well:
Array.prototype.select = function(expr){
var arr = this;
//do custom stuff
return arr.map(expr); //or $.map(expr);
};
var ids = this.fruits.select(function(v){
return v.Id;
});
An extended version that uses the function ...
How do I use extern to share variables between source files?
...e protected against reinclusion, so that type
definitions (enum, struct or union types, or typedefs generally) do not
cause problems. The standard technique is to wrap the body of the
header in a header guard such as:
#ifndef FILE3B_H_INCLUDED
#define FILE3B_H_INCLUDED
...contents of header...
#e...
How do I query between two dates using MySQL?
...ember 29 2010 and January 30 2010). Try reversing the order of the dates:
SELECT *
FROM `objects`
WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55')
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How to generate the “create table” sql statement for an existing table in postgreSQL
... text;
column_record record;
BEGIN
FOR column_record IN
SELECT
b.nspname as schema_name,
b.relname as table_name,
a.attname as column_name,
pg_catalog.format_type(a.atttypid, a.atttypmod) as column_type,
CASE WHEN
...