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MySQL select with CONCAT condition
...available within the query itself.
You can either repeat the expression:
SELECT neededfield, CONCAT(firstname, ' ', lastname) as firstlast
FROM users
WHERE CONCAT(firstname, ' ', lastname) = "Bob Michael Jones"
or wrap the query
SELECT * FROM (
SELECT neededfield, CONCAT(firstname, ' ', last...
How to declare variable and use it in the same Oracle SQL script?
...; exec :name := 'SALES'
PL/SQL procedure successfully completed.
SQL> select * from dept
2 where dname = :name
3 /
DEPTNO DNAME LOC
---------- -------------- -------------
30 SALES CHICAGO
SQL>
A VAR is particularly useful when we want to call a stored...
How do you use the “WITH” clause in MySQL?
...s mentioned, you provided a poor example - there's no need to perform a subselect if you aren't altering the output of the columns in any way:
SELECT *
FROM ARTICLE t
JOIN USERINFO ui ON ui.user_userid = t.article_ownerid
JOIN CATEGORY c ON c.catid = t.article_categoryid
WHERE t....
Most efficient way to concatenate strings?
What's the most efficient way to concatenate strings?
17 Answers
17
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MySQL and GROUP_CONCAT() maximum length
...You should use it like this.
SET SESSION group_concat_max_len = 1000000;
select group_concat(column) from table group by column
You can do this even in sharing hosting, but when you use an other session, you need to repeat the SET SESSION command.
...
Include headers when using SELECT INTO OUTFILE?
...
You'd have to hard code those headers yourself. Something like:
SELECT 'ColName1', 'ColName2', 'ColName3'
UNION ALL
SELECT ColName1, ColName2, ColName3
FROM YourTable
INTO OUTFILE '/path/outfile'
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Elegant way to combine multiple collections of elements?
...in a collection (e.g., of type List<List<int>> , I could use SelectMany to combine them all into one collection.
...
How do I concatenate multiple C++ strings on one line?
C# has a syntax feature where you can concatenate many data types together on 1 line.
24 Answers
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How can I concatenate two arrays in Java?
I need to concatenate two String arrays in Java.
61 Answers
61
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MySQL combine two columns into one column
...does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two ways to add a space:
select concat(column1, ' ', column2)
select concat_ws(' ', column1, column2)
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