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MySQL: Large VARCHAR vs. TEXT?
I've got a messages table in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserte...
Convert from MySQL datetime to another format with PHP
I have a datetime column in MySQL.
18 Answers
18
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error, string or binary data would be truncated when trying to insert
... and the reason was that in an INSERT statement that received data from an UNION, the order of the columns was different from the original table. If you change the order in #table3 to a, b, c, you will fix the error.
select a, b, c into #table1
from #table0
insert into #table1
select a, b, c f...
MySQL select one column DISTINCT, with corresponding other columns
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@Full Decent you can't, according to MySQL documentation: "The server is free to choose any value from each group, so unless they are the same, the values chosen are indeterminate.". In practice I've successfully used this kind of queries with ORDER BY clause, ...
ERROR: Error 1005: Can't create table (errno: 121)
I have troubles with forward engineering my MySQL database into WAMP server..
I was going to post an image of the schema but as this is my first post I can't.
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Does MySQL index foreign key columns automatically?
Does MySQL index foreign key columns automatically?
9 Answers
9
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MySQL Conditional Insert
...his, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the values are not already found.
Alternatively, look at the MERGE statement.
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Real life example, when to use OUTER / CROSS APPLY in SQL
...o2, Bar2),
(Foo3, Bar3)) V(Foo, Bar);
In 2005 UNION ALL can be used instead.
SELECT Id,
Foo,
Bar
FROM T
CROSS APPLY (SELECT Foo1, Bar1
UNION ALL
SELECT Foo2, Bar2
UNION ALL
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How do I enlarge an EER Diagram in MySQL Workbench?
I am working on a moderately complex schema in MySQL Workbench, and the single page of the EER diagram is now full up. Does anyone know how to enlarge it to two or more pages?
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How to do a regular expression replace in MySQL?
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With MySQL 8.0+ you could use natively REGEXP_REPLACE function.
12.5.2 Regular Expressions:
REGEXP_REPLACE(expr, pat, repl[, pos[, occurrence[, match_type]]])
Replaces occurrences in the string expr that match the regular express...