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MySQL Conditional Insert
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If your DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHE...
How to work around the stricter Java 8 Javadoc when using Maven
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Note that for the error no summary or caption for table, using <table summary=""> won't work anymore. If that's your situation, add a <caption> element to your table, like this:
<table>
<caption>Examples</caption>
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</table>
H...
Open-sided Android stroke?
...fill_parent"
android:layout_height="0dp"
android:layout_below="@id/table_options"
android:layout_above="@id/exit_bar"/>
Which fills the gap between table_options and exit_bar with a background and just before exit_bar prints a 1dp line. This did the trick for me, I hope it helps som...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...ent one-to-one, one-to-many and many-to-many relationships while designing tables with some examples?
4 Answers
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Select rows which are not present in other table
I've got two postgresql tables:
4 Answers
4
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How to make a JTable non-editable
How to make a JTable non-editable? I don't want my users to be able to edit the values in cells by double-clicking them.
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...eatly slows down the performance. (In contrast, Intel C++ Compiler , executable icc , will eliminate the library call for pow(a,6) .)
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How do I find which transaction is causing a “Waiting for table metadata lock” state?
I am trying to perform some DDL on a table and SHOW PROCESSLIST results in a " Waiting for table metadata lock " message.
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Can you do this HTML layout without using tables?
... are available to you to do the job quickly and correctly.
In this case a table worked perfectly.
I personally would have used a table for this.
I think nested tables should be avoided, things can get messy.
share
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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...OUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those rare cases is equivalent to count(*)
Use count(*) for counting
U...