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SQL to find the number of distinct values in a column
...aggregate function:
SELECT COUNT(DISTINCT column_name) AS some_alias FROM table_name
This will count only the distinct values for that column.
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How do exceptions work (behind the scenes) in c++
...atching_functionv, .-_Z20my_catching_functionv
.section .gcc_except_table,"a",@progbits
.align 4
.LLSDA9:
.byte 0xff
.byte 0x0
.uleb128 .LLSDATT9-.LLSDATTD9
.LLSDATTD9:
.byte 0x1
.uleb128 .LLSDACSE9-.LLSDACSB9
.LLSDACSB9:
.uleb128 .LEHB0-.LFB9
.uleb128 .L...
Random row from Linq to Sql
...dom()
select row).FirstOrDefault();
Note that this is only suitable for small-to-mid-size tables; for huge tables, it will have a performance impact at the server, and it will be more efficient to find the number of rows (Count), then pick one at random (Skip/First).
for count approa...
How do I keep two side-by-side divs the same height?
... How do you define the cell padding you actually want present in the table cell, eg padding: 7px 10px, if the padding-bottom property is set to 100%? (PS overflow:hidden was also required for me on the row)
– user1063287
Mar 19 '18 at 4:23
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Sorting arrays in NumPy by column
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You can sort on multiple columns as per Steve Tjoa's method by using a stable sort like mergesort and sorting the indices from the least significant to the most significant columns:
a = a[a[:,2].argsort()] # First sort doesn't need to be stable.
a = a[a[:,1].argsort(kind='mergesort')]
a = a[a[:,...
Check if a row exists, otherwise insert
I need to write a T-SQL stored procedure that updates a row in a table. If the row doesn't exist, insert it. All this steps wrapped by a transaction.
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SQL Server - SELECT FROM stored procedure
...ure can return multiple result sets, each with its own schema. It's not suitable for using in a SELECT statement.
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Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
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You have a mismatch of two different collations in your table. You can check what collations each column in your table(s) has by using this query:
SELECT
col.name, col.collation_name
FROM
sys.columns col
WHERE
object_id = OBJECT_ID('YourTableName')
Collations are n...
Sequelize Unknown column '*.createdAt' in 'field list'
...he error is that you have timestamps enabled in sequelize, but your actual table definitions in the DB do not contain a timestamp column.
When you do user.find it will just do SELECT user.*, which only takes the columns you actually have. But when you join, each column of the joined table will be a...
Accessing Google Spreadsheets with C# using Google Data API
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Ultimately I need to get the information from Google spreadsheet in a DataTable.
How can I do it? If anyone has attempted it, pls share some information.
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