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java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'

...rs and one will see squares if you are not using fonts that support them. MySQL's utf8 only supports basic multilingual plane, and you need to use utf8mb4 instead: For a supplementary character, utf8 cannot store the character at all, while utf8mb4 requires four bytes to store it. Since utf8 ...
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How big can a MySQL database get before performance starts to degrade

At what point does a MySQL database start to lose performance? 15 Answers 15 ...
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Change MySQL default character set to UTF-8 in my.cnf?

...want to add the following to my.cnf [client] default-character-set=utf8 [mysql] default-character-set=utf8 [mysqld] collation-server = utf8_unicode_ci init-connect='SET NAMES utf8' character-set-server = utf8 If you want to change the character set for an existing DB, let me know... your quest...
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Retrieve the maximum length of a VARCHAR column in SQL Server

... Use the built-in functions for length and max on the description column: SELECT MAX(LEN(DESC)) FROM table_name; Note that if your table is very large, there can be performance issues. share | im...
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How to get UTF-8 working in Java webapps?

...s" those characters. To get UTF-8 working under Java+Tomcat+Linux/Windows+Mysql requires the following: Configuring Tomcat's server.xml It's necessary to configure that the connector uses UTF-8 to encode url (GET request) parameters: <Connector port="8080" maxHttpHeaderSize="8192" maxThreads...
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How to fix Error: “Could not find schema information for the attribute/element” by creating schema

...tudio, open your app.config or web.config file. Go to the "XML" menu and select "Create Schema". This action should create a new file called "app.xsd" or "web.xsd". Save that file to your disk. Go back to your app.config or web.config and in the edit window, right click and select properties. From...
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JPA: what is the proper pattern for iterating over large result sets?

...essSession(); Query query = session .createQuery("SELECT a FROM Address a WHERE .... ORDER BY a.id"); query.setFetchSize(Integer.valueOf(1000)); query.setReadOnly(true); query.setLockMode("a", LockMode.NONE); ScrollableResults results = query....
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How to change the output color of echo in Linux

...use different numbers, not given here. Text mode commands tput bold # Select bold mode tput dim # Select dim (half-bright) mode tput smul # Enable underline mode tput rmul # Disable underline mode tput rev # Turn on reverse video mode tput smso # Enter standout (bold) mode tput...
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List of Big-O for PHP functions

...: isset/array_key_exists is much faster than in_array and array_search +(union) is a bit faster than array_merge (and looks nicer). But it does work differently so keep that in mind. shuffle is on the same Big-O tier as array_rand array_pop/array_push is faster than array_shift/array_unshift due t...
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How do I find duplicate values in a table in Oracle?

...then use a HAVING clause to find values that appear greater than one time. SELECT column_name, COUNT(column_name) FROM table_name GROUP BY column_name HAVING COUNT(column_name) > 1; share | impr...