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Finding duplicate values in a SQL table
...
SELECT
name, email, COUNT(*)
FROM
users
GROUP BY
name, email
HAVING
COUNT(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY ...
How to list the tables in a SQLite database file that was opened with ATTACH?
...quently, if you used
ATTACH some_file.db AS my_db;
then you need to do
SELECT name FROM my_db.sqlite_master WHERE type='table';
Note that temporary tables don't show up with .tables either: you have to list sqlite_temp_master for that:
SELECT name FROM sqlite_temp_master WHERE type='table';
...
What does the 'b' character do in front of a string literal?
...nce of the bytes type instead of the str type. They may only contain ASCII characters; bytes with a numeric value of 128 or greater must be expressed with escapes.
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Acronyms in CamelCase [closed]
...n using acronyms, use Pascal case or camel case for acronyms more than two characters long. For example, use HtmlButton or htmlButton. However, you should capitalize acronyms that consist of only two characters, such as System.IO instead of System.Io.
Do not use abbreviations in identifiers or ...
sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and t
...this is giving me the error, The actual string I am trying to insert is 74 chars long, it's: "/gifs/epic-fail-photos-there-i-fixed-it-aww-man-the-tire-pressures-low.gif"
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What's the best UI for entering date of birth? [closed]
What is the best method for date of birth selector?
24 Answers
24
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Trying to embed newline in a variable in bash [duplicate]
...rting \n
p="${var1}\n${var2}"
echo -e "${p}"
echo -e interprets the two characters "\n" as a new line.
var="a b c"
first_loop=true
for i in $var
do
p="$p\n$i" # Append
unset first_loop
done
echo -e "$p" # Use -e
Avoid extra leading newline
var="a b c"
first_loop=1...
Check for changes to an SQL Server table?
...
Take a look at the CHECKSUM command:
SELECT CHECKSUM_AGG(BINARY_CHECKSUM(*)) FROM sample_table WITH (NOLOCK);
That will return the same number each time it's run as long as the table contents haven't changed. See my post on this for more information:
CHECKSUM...
Duplicating a MySQL table, indices, and data
...ese 2 queries:
CREATE TABLE newtable LIKE oldtable;
INSERT INTO newtable SELECT * FROM oldtable;
To copy just structure and data use this one:
CREATE TABLE tbl_new AS SELECT * FROM tbl_old;
I've asked this before:
Copy a MySQL table including indexes
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MySQL: Quick breakdown of the types of joins [duplicate]
...es
END EDIT
In a nutshell, the comma separated example you gave of
SELECT * FROM a, b WHERE b.id = a.beeId AND ...
is selecting every record from tables a and b with the commas separating the tables, this can be used also in columns like
SELECT a.beeName,b.* FROM a, b WHERE b.id = a.beeId...