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    <p>DOUBLE columns are <strong>not</strong> the same as DECIMAL columns, and you <strong>will get in trouble</strong> if you use DOUBLE columns for financial data.</p> <p>DOUBLE is actually just a double precision (64 bit instead of 32 bit) version of <a href="http://en.wikipedia.org/wiki/Floating_point" rel="noreferrer">FLOAT</a>. Floating point numbers are approximate representations of <a href="http://en.wikipedia.org/wiki/Real_number" rel="noreferrer">real numbers</a> and they are not exact. In fact, simple numbers like 0.01 do not have an exact representation in FLOAT or DOUBLE types.</p> <p>DECIMAL columns are exact representations, but they take up a lot more space for a much smaller range of possible numbers. To create a column capable of holding values from 0.0001 to 99.9999 like you asked you would need the following statement</p> <pre><code>CREATE TABLE your_table ( your_column DECIMAL(6,4) NOT NULL ); </code></pre> <p>The column definition follows the format DECIMAL(M, D) where <em>M</em> is the maximum number of digits (the <em>precision</em>) and <em>D</em> is the number of digits to the right of the decimal point (the <em>scale</em>). </p> <p>This means that the previous command creates a column that accepts values from -99.9999 to 99.9999. You may also create an UNSIGNED DECIMAL column, ranging from 0.0000 to 99.9999.</p> <p>For more information on MySQL DECIMAL the <a href="http://dev.mysql.com/doc/refman/5.1/en/precision-math-decimal-characteristics.html" rel="noreferrer">official docs</a> are always a great resource.</p> <p>Bear in mind that all of this information is true for versions of MySQL 5.0.3 and greater. If you are using previous versions, you really should upgrade.</p>
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    1. POHow to use MySQL DECIMAL?
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    1. USAlex Recarey
    1. USAlex Recarey
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    1. COVoted up your answer. Your answer is correct, the other answer is not (since it claims that "double = decimal"). DECIMAL is a fixed-point type with an exact value and its synonyms are NUMERIC, DEC and FIXED. Not DOUBLE, because DOUBLE is a floating-point type that represents approximate numeric data values. When using DECIMAL(<1-65>, <0-30>), the first parameter is the number of digits, the second the number of digits to the right of the decimal point.
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      1. USNorbert
    2. COYes, you are right. Take note that is work for MySQL 5.0.3 onwards, http://dev.mysql.com/doc/refman/5.1/en/precision-math-examples.html
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    3. CO@ajreal - could you amend your answer accordingly? Thanks in advance.
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