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MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
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How do I format date and time on ssrs report?
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Hope this helps:
SELECT convert(varchar, getdate(), 100) -- mon dd yyyy hh:mmAM
SELECT convert(varchar, getdate(), 101) -- mm/dd/yyyy – 10/02/2008
SELECT convert(varchar, getdate(), 102) -- yyyy.mm.dd – 2008.10.02 ...
Insert into … values ( SELECT … FROM … )
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Try:
INSERT INTO table1 ( column1 )
SELECT col1
FROM table2
This is standard ANSI SQL and should work on any DBMS
It definitely works for:
Oracle
MS SQL Server
MySQL
Postgres
SQLite v3
Teradata
DB2
Sybase
Vertica
HSQLDB
H2
AWS RedShift
SA...
Android Spinner: Get the selected item change event
How can you set the event listener for a Spinner when the selected item changes?
16 Answers
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MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
How do I use ROW_NUMBER()?
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For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Ro...
How do I do top 1 in Oracle?
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If you want just a first selected row, you can:
select fname from MyTbl where rownum = 1
You can also use analytic functions to order and take the top x:
select max(fname) over (rank() order by some_factor) from MyTbl
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How do I check to see if a value is an integer in MySQL?
...e REGEXP operator, matching the string to a regular expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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What is the purpose of Order By 1 in SQL select statement?
...number stands for the column based on the number of columns defined in the SELECT clause. In the query you provided, it means:
ORDER BY A.PAYMENT_DATE
It's not a recommended practice, because:
It's not obvious/explicit
If the column order changes, the query is still valid so you risk ordering ...
What is the difference between “INNER JOIN” and “OUTER JOIN”?
...he intersection of the two tables, i.e. the two rows they have in common.
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUT...