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Query to count the number of tables I have in MySQL

... SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'dbName'; Source This is mine: USE databasename; SHOW TABLES; SELECT FOUND_ROWS(); ...
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How important is the order of columns in indexes?

I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example: ...
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Rename package in Android Studio

...n: In your Project pane, click on the little gear icon ( ) Uncheck / De-select the Compact Empty Middle Packages option Your package directory will now be broken up in individual directories Individually select each directory you want to rename, and: Right-click it Select Refactor Click o...
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How to check if a table exists in a given schema

... whether a table (or view) exists, and the current user has access to it? SELECT EXISTS ( SELECT FROM information_schema.tables WHERE table_schema = 'schema_name' AND table_name = 'table_name' ); The information schema is mainly useful to stay portable across major versions and...
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MySQL JOIN the most recent row only?

... You may want to try the following: SELECT CONCAT(title, ' ', forename, ' ', surname) AS name FROM customer c JOIN ( SELECT MAX(id) max_id, customer_id FROM customer_data GROUP BY customer_id ...
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How to display default text “--Select Team --” in combo box on pageload in WPF?

...ComboBox Name="MyComboBox" IsEditable="True" IsReadOnly="True" Text="-- Select Team --" /> You'll obviously need to add your other options, but this is probably the simplest way to do it. There is however one downside to this method which is while the text inside your combo box will not be ...
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Can we have multiple “WITH AS” in single sql - Oracle SQL

... You can do this as: WITH abc AS( select FROM ...) , XYZ AS(select From abc ....) /*This one uses "abc" multiple times*/ Select From XYZ.... /*using abc, XYZ multiple times*/ ...
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SQL DROP TABLE foreign key constraint

...your table, you could use this SQL (if you're on SQL Server 2005 and up): SELECT * FROM sys.foreign_keys WHERE referenced_object_id = object_id('Student') and if there are any, with this statement here, you could create SQL statements to actually drop those FK relations: SELECT 'ALTER TABL...
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Emacs on Mac OS X Leopard key bindings

... ⌘ + → - move to end of current line Shift + any of the above extend selection by appropriate amount Click then drag - select text Double-click then drag - select text, wrapping to word ends Triple-click then drag - select text, wrapping to paragraph ends Shift + Select text with mouse - add...
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How to paste text to end of every line? Sublime 2

... Yeah Regex is cool, but there are other alternative. Select all the lines you want to prefix or suffix Goto menu Selection -> Split into Lines (Cmd/Ctrl + Shift + L) This allows you to edit multiple lines at once. Now you can add *Quotes (") or anything * at start and end...