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How can I export the schema of a database in PostgreSQL?

...ed formats --lock-wait-timeout=TIMEOUT fail after waiting TIMEOUT for a table lock -?, --help show this help, then exit Options controlling the output content: -a, --data-only dump only the data, not the schema -b, --blobs include large objec...
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Is there a way to get a collection of all the Models in your Rails app?

... ActiveRecord::Base.connection.tables.map do |model| model.capitalize.singularize.camelize end will return ["Article", "MenuItem", "Post", "ZebraStripePerson"] Additional information If you want to call a method on the object name without model:stri...
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MySQL INNER JOIN select only one row from second table

I have a users table and a payments table, for each user, those of which have payments, may 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 sta...
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What's the difference between echo, print, and print_r in PHP?

...ing No return value var_export() Outputs a human-readable and PHP-executable representation of any one value Accepts not just strings but other types including arrays and objects, formatting them to be readable Uses a different output format to both print_r() and var_dump() - resulting output is...
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How to center an element horizontally and vertically

...y/horizontally centered!</span> </div> Approach 3 - table-cell/vertical-align: middle: Example Here / Full Screen Example In some cases, you will need to ensure that the html/body element's height is set to 100%. For vertical alignment, set the parent element's width/height...
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jQuery: count number of rows in a table

How do I count the number of tr elements within a table using jQuery? 11 Answers 11 ...
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T-SQL: Deleting all duplicate rows but keeping one [duplicate]

I have a table with a very large amount of rows. Duplicates are not allowed but due to a problem with how the rows were created I know there are some duplicates in this table. I need to eliminate the extra rows from the perspective of the key columns. Some other columns may have slightly different...
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Python integer incrementing with ++ [duplicate]

...sistency. That's one of the design decisions. And because integers are immutable, the only way to 'change' a variable is by reassigning it. Fortunately we have wonderful tools for the use-cases of ++ and -- in other languages, like enumerate() and itertools.count(). ...
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Delete all Duplicate Rows except for One in MySQL? [duplicate]

How would I delete all duplicate data from a MySQL Table? 2 Answers 2 ...
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How to store arrays in MySQL?

I have two tables in MySQL. Table Person has the following columns: 7 Answers 7 ...