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Simplest way to do a recursive self-join?
What is the simplest way of doing a recursive self-join in SQL Server? I have a table like this:
5 Answers
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Add a column to a table, if it does not already exist
I want to write a query for MS SQL Server that adds a column into a table. But I don't want any error display, when I run/execute the following query.
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Find nearest latitude/longitude with an SQL query
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Google's solution:
Creating the Table
When you create the MySQL table, you want to pay particular attention to the lat and lng attributes. With the current zoom capabilities of Google Maps, you should only need 6 digits of precision after the decimal. To keep the storage space require...
Does Foreign Key improve query performance?
...Keys are a referential integrity tool, not a performance tool. At least in SQL Server, the creation of an FK does not create an associated index, and you should create indexes on all FK fields to improve look up times.
shar...
LINQ to SQL - Left Outer Join with multiple join conditions
I have the following SQL, which I am trying to translate to LINQ:
6 Answers
6
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Generating a UUID in Postgres for Insert statement?
...default. You must load it into your database to use it.
For modern PostgreSQL versions (9.1 and newer) that's easy:
CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
but for 9.0 and below you must instead run the SQL script to load the extension. See the documentation for contrib modules in 8.4.
For...
Better techniques for trimming leading zeros in SQL Server?
...rflow.com/questions/662383/better-techniques-for-trimming-leading-zeros-in-sql-server
DECLARE @retVal VarChar(128),
@pattern varChar(10)
SELECT @pattern = '%[^'+@stripChar+']%'
SELECT @retVal = CASE WHEN SUBSTRING(@string, PATINDEX(@pattern, @string+'.'), LEN(@string)) = '' T...
How to force LINQ Sum() to return 0 while source collection is empty
... handled method by the EF Queryable Provider and will generate the related SQL statement.
– Simon Belanger
Aug 11 '15 at 1:52
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MySQL query to get column names?
I'd like to get all of a mysql table's col names into an array in php?
21 Answers
21
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sql ORDER BY multiple values in specific order?
Ok I have a table with a indexed key and a non indexed field.
I need to find all records with a certain value and return the row.
I would like to know if I can order by multiple values.
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