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How to select date from datetime column?
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You can use MySQL's DATE() function:
WHERE DATE(datetime) = '2009-10-20'
You could also try this:
WHERE datetime LIKE '2009-10-20%'
See this answer for info on the performance implications of using LIKE.
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How to convert an image to base64 encoding?
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Here is the code for upload to encode and save it to the MySQL
if (!isset($_GET["getfile"])) {
if ($_FILES["file"]["error"] > 0) {
echo "Error: " . $_FILES["file"]["error"] . "<br>";
} else {
move_uploaded_file($_FILES["file"]["tmp_name"], $_FILES[...
Get query from java.sql.PreparedStatement [duplicate]
...To my experience, the ones which do so are at least the PostgreSQL 8.x and MySQL 5.x JDBC drivers. For the case your JDBC driver doesn't support it, your best bet is using a statement wrapper which logs all setXxx() methods and finally populates a SQL string on toString() based on the logged informa...
How do I escape reserved words used as column names? MySQL/Create Table
...and one problem is a class may have a field name key which is a reserved MySQL keyword. How do I escape it in a create table statement? (Note: The other problem below is text must be a fixed size to be indexed/unique)
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Is there an SQLite equivalent to MySQL's DESCRIBE [table]?
... SQLite . It would be nice to be able to see the details for a table, like MySQL's DESCRIBE [table] . PRAGMA table_info [table] isn't good enough, as it only has basic information (for example, it doesn't show if a column is a field of some sort or not). Does SQLite have a way to do this?
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“21天教你学会C++” - 创意 - 清泛网 - 专注C/C++及内核技术
...法（如果你已经会一门类似的语言），但你无法学到多少如何运用这些语法。简而言之，如果你是，比如说一个Basic程序员，你可以学会用C++语法写出Basic风格的程序，但你学不到C++真正的优点（和缺点）。那关键在哪里？Alan Per...
When to use single quotes, double quotes, and backticks in MySQL
...le and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommended to avoid using reserved keywords as column or table identifiers when possibl...
Inserting a Python datetime.datetime object into MySQL
I have a date column in a MySQL table. I want to insert a datetime.datetime() object into this column. What should I be using in the execute statement?
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UTF-8 all the way through
...character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly use utf8mb4 encoding if a utf8mb4_* collation is specified (without any explicit character set).
In older versions of MyS...
What is cardinality in MySQL?
What is cardinality in MySQL? Please explain in simple, non-technical language.
8 Answers
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