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Using Java to find substring of a bigger string using Regular Expression
...ch would handle nested brackets. Additionally, I believe using the indexOf(char) would be faster than indexOf(String).
– Hosam Aly
Mar 2 '09 at 11:03
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What does it mean by select 1 from table?
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SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, c...
How to select only date from a DATETIME field in MySQL?
...e a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
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MySQL INNER JOIN select only one row from second table
...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
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MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
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What is the reason not to use select *?
...eople claim that you should specifically name each column you want in your select query.
20 Answers
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is it possible to select EXISTS directly as a bit?
...workaround.
If you must return a conditional bit 0/1 another way is to:
SELECT CAST(
CASE WHEN EXISTS(SELECT * FROM theTable where theColumn like 'theValue%') THEN 1
ELSE 0
END
AS BIT)
Or without the cast:
SELECT
CASE
WHEN EXISTS( SELECT 1 FROM theTable WHERE theColumn LI...
Difference between Select Unique and Select Distinct
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SELECT UNIQUE is old syntax supported by Oracle's flavor of SQL. It is synonymous with SELECT DISTINCT.
Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than ...
Getting the minimum of two values in SQL
...led OwedPast . They are both results of some subqueries in SQL. How can I select the smaller of the two and return it as a value titled PaidForPast ?
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Insert a string at a specific index
...ice() method changes the content of a string by removing a range of
* characters and/or adding new characters.
*
* @this {String}
* @param {number} start Index at which to start changing the string.
* @param {number} delCount An integer indicating the number of old chars to ...