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Inserting multiple rows in a single SQL query? [duplicate]
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@ahnbizcad Semicolons in T-sql are USUALLY optional, but they are reported to be required in the future. You should get yourself in the habit of using them to terminate each statement--your code will look nicer too IMO.
– NReilingh
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How to disable text selection highlighting
... a CSS standard way to disable the highlighting effect if the user accidentally selects the text?
48 Answers
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Performance of FOR vs FOREACH in PHP
First of all, I understand in 90% of applications the performance difference is completely irrelevant, but I just need to know which is the faster construct. That and...
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When should I use a NoSQL database instead of a relational database? Is it okay to use both on the s
...proven and suitable for 99% of the real world applications. You can practically do anything with relational databases.
But, there are limitations on speed and scaling when it comes to massive high availability data stores. For example, Google and Amazon have terabytes of data stored in big data cen...
Limit text length to n lines using CSS
...limit a text length to "n" lines using CSS (or cut it when overflows vertically).
13 Answers
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Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSER...
Docker build “Could not resolve 'archive.ubuntu.com'” apt-get fails to install anything
... 8.8.8.8
Address 1: 8.8.8.8
If the command appears to hang, but eventually spits out the error "can't resolve 'google.com'", then you have the same problem as me.
The nslookup command queries the DNS server 8.8.8.8 in order to turn the text address of 'google.com' into an IP address. Ironicall...
Is there a difference between foreach and map?
...important point to mention (this is particularly true in Scala) is that a call to map does not result in the execution of its underlying logic until when the expected transformed list is summoned. In contrast, foreach's operation is computed immediately.
– solimant
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Lock Escalation - What's happening here?
... to take fewer, larger locks (e.g. entire table) instead of locking many smaller things (e.g. row locks).
But this can be problematic when you have a huge table, because taking a lock on the entire table may lock out other queries for a long time. That's the tradeoff: many small-granularity locks...
Get current value of a setting in Vim
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If you don't remember what setting you want to check, you can view all settings:
:set all
or show each setting, one setting per line:
:set! all
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