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How do I get SUM function in MySQL to return '0' if no values are found?
...Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nulls, and one with a mixture):
SQL Fidd...
How To Change DataType of a DataColumn in a DataTable?
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You cannot change the DataType after the Datatable is filled with data. However, you can clone the Data table, change the column type and load data from previous data table to the cloned table as shown below.
DataTable dtCloned = dt.Clone();
dtCloned.Columns[0].DataTyp...
Lua简明教程 - 脚本技术 - 清泛IT论坛，有思想、有深度
...unction foo(x) return x^2 end
foo = function(x) return x^2 end复制代码
Table所谓Table其实就是一个Key Value的数据结构，它很像Javascript中的Object，或是PHP中的数组，在别的语言里叫Dict或Map，Table长成这个样子：haoel = {name="ChenHao", age=37, han...
resizes wrong; appears to have unremovable `min-width: min-content`
...nge the display property of the fieldset to one of the following values:
table-cell (recommended)
table-column
table-column-group
table-footer-group
table-header-group
table-row
table-row-group
Of these, I recommend table-cell. Both table-row and table-row-group prevent you from changing width, ...
Export Postgresql table data using pgAdmin
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Just right click on a table and select "backup". The popup will show various options, including "Format", select "plain" and you get plain SQL.
pgAdmin is just using pg_dump to create the dump, also when you want plain SQL.
It uses something lik...
Is it possible to use the SELECT INTO clause with UNION [ALL]?
In SQL Server this inserts 100 records, from the Customers table into tmpFerdeen :-
8 Answers
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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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How to calculate percentage with a SQL statement
I have a SQL Server table that contains users & their grades. For simplicity's sake, lets just say there are 2 columns - name & grade . So a typical row would be Name: "John Doe", Grade:"A".
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Export from sqlite to csv using shell script
... sqlite3 command options:
sqlite3 -header -csv my_db.db "select * from my_table;" > out.csv
This makes it a one-liner.
Also, you can run a sql script file:
sqlite3 -header -csv my_db.db < my_script.sql > out.csv
Use sqlite3 -help to see the list of available options.
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How to prevent text in a table cell from wrapping
Does anyone know how I can prevent the text in a table cell from wrapping? This is for the header of a table, and the heading is a lot longer than the data under it, but I need it to display on only one line. It is okay if the column is very wide.
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