Produces a TIME value. Produces a YEAR value. These rules govern conversion to YEAR :. For a four-digit number in the range inclusive, or for a string which can be interpreted as a four-digit number in this range, return the corresponding YEAR value.
For a number consisting of one or two digits, or for a string which can be interpeted as such a number, return a YEAR value as follows:. If the number is in the range inclusive, add and return the sum. For a TIME value, return the current year. If you do not specify the type of a TIME argument, you may get a different result from what you expect, as shown here:.
A string value containing non-numeric characters which must be truncated prior to conversion raises a warning, as shown here:. In MySQL 8. ARRAY is not supported except when used to create a multi-valued index in one of these statements, in which case it is required. The column being indexed must be a column of type JSON.
For syntax information and examples, as well as other relevant information, see Multi-Valued Indexes. Beginning with MySQL 8. In MySQL, transcoding names are the same as the corresponding character set names. For example, this statement converts the string 'abc' in the default character set to the corresponding string in the utf8mb4 character set:.
For more information, see the description of CAST. For example, these are legal:. For string literals, another way to specify the character set is to use a character set introducer. Unlike conversion functions such as CAST , or CONVERT , which convert a string from one character set to another, an introducer designates a string literal as having a particular character set, with no conversion involved. For more information, see Section Normally, you cannot compare a BLOB value or other binary string in case-insensitive fashion because binary strings use the binary character set, which has no collation with the concept of lettercase.
Comparisons of the resulting string use its collation. For example, if the conversion result collation is not case-sensitive, a LIKE operation is not case-sensitive. To use a different character set, substitute its name for utf8mb4 in the preceding statements and similarly to use a different collation. For example, a comparison of these strings results in an error because they have different character sets:.
Converting one of the strings to a character set compatible with the other enables the comparison to occur without error:.
Character set conversion is also useful preceding lettercase conversion of binary strings. To perform lettercase conversion of a binary string, first convert it to a nonbinary string using a character set appropriate for the data stored in the string:. In spatial casts, GeometryCollection and GeomCollection are synonyms for the same result type. Some conditions apply to all spatial type casts, and some conditions apply only when the cast result is to have a particular spatial type.
General Conditions for Spatial Casts. Conditions for Casts to Point. Conditions for Casts to LineString. Conditions for Casts to Polygon. Conditions for Casts to MultiPoint. Conditions for Casts to MultiLineString. Conditions for Casts to MultiPolygon. Conditions for Casts to GeometryCollection. The result of a cast is in the same SRS as that of the expression to cast. Casting between spatial types does not change coordinate values or order.
If the expression to cast has a geographic SRS but has a longitude or latitude that is out of range, an error occurs:. Ranges shown are in degrees. If an SRS uses another unit, the range uses the corresponding values in its unit. The exact range limits deviate slightly due to floating-point arithmetic. When the cast result type is Point , these conditions apply:. If the expression to cast is a well-formed geometry of type Point , the function result is that Point. If the expression to cast is a well-formed geometry of type MultiPoint containing a single Point , the function result is that Point.
If the expression to cast is a well-formed geometry of type GeometryCollection containing only a single Point , the function result is that Point. When the cast result type is LineString , these conditions apply:.
If the expression to cast is a well-formed geometry of type LineString , the function result is that LineString. If the expression to cast is a well-formed geometry of type Polygon that has no inner rings, the function result is a LineString containing the points of the outer ring in the same order.
If the expression to cast is a well-formed geometry of type MultiPoint containing at least two points, the function result is a LineString containing the points of the MultiPoint in the order they appear in the expression. If the expression to cast is a well-formed geometry of type MultiLineString containing a single LineString , the function result is that LineString. If the expression to cast is a well-formed geometry of type GeometryCollection , containing only a single LineString , the function result is that LineString.
When the cast result type is Polygon , these conditions apply:. If the expression to cast is a well-formed geometry of type LineString that is a ring that is, the start and end points are the same , the function result is a Polygon with an outer ring consisting of the points of the LineString in the same order.
If the expression to cast is a well-formed geometry of type Polygon , the function result is that Polygon. Gary Gary 4 4 silver badges 12 12 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Stack Gives Back Safety in numbers: crowdsourcing data on nefarious IP addresses. Featured on Meta. New post summary designs on greatest hits now, everywhere else eventually.
Related 3. Asked 7 years, 3 months ago. Active 7 years, 3 months ago. Viewed 69k times. DATE expr : Extracts the date part of the date or datetime expression expr. Improve this question. Community Bot 1 1 1 silver badge. The supported range is '' to ''". Also I've added my results for the zero date. I know this doesn't answer the question you asked, but could I suggest using unix timestamps instead of dates? The datatype of your column would be a bigint. My question applies regardless of whether I'm working with dates, times, or dates and times.
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