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3 min readTo sum a UNION ALL subquery in Oracle, you can encapsulate the subquery within a larger query and use the SUM function to calculate the total of the result set. The UNION ALL operator is used to combine the results of multiple queries into a single result set. By using the SUM function on the encapsulating query, you can calculate the total sum of the combined subquery results. Remember to give an alias to the sum column to make it more readable in the output.
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6 min readTo convert a number to a date time in Oracle, you can use the TO_DATE function. This function takes two arguments: the number you want to convert and the format in which you want the date time to be displayed. For example, if you have a number representing a Unix timestamp, you can convert it to a date time by using the TO_DATE function with the appropriate format string. Alternatively, you can use the TO_TIMESTAMP function if the number represents a timestamp in a specific format.
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3 min readTo convert a varchar to a number in Oracle, you can use the TO_NUMBER function. This function converts a character string into a number. The syntax for the TO_NUMBER function is: TO_NUMBER(input_string, format_mask) where input_string is the varchar that you want to convert to a number and format_mask specifies the format of the input_string. The format_mask is optional and can be used to control the conversion process. If you do not provide a format_mask, Oracle will use the default format.
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2 min readTo concatenate strings in Oracle, you can use the || operator. This operator allows you to combine multiple strings into one. For example, if you want to concatenate the strings 'Hello' and 'World', you can do so like this:SELECT 'Hello' || 'World' FROM dual;This will result in the output 'HelloWorld'. You can also concatenate column values from a table by using the || operator in a SELECT statement.
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5 min readIn pandas, you can extend multilevel columns by creating a list of tuples to define the multi-level index. This can be achieved by setting the "columns" attribute of a DataFrame or by using the "MultiIndex.from_tuples" method. This allows you to represent multiple levels of columns in a DataFrame, which can be useful for organizing and analyzing complex data structures.
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5 min readTo convert an XMLType data type to a VARCHAR data type in Oracle, you can use the getStringVal() method. This method returns the XMLType data as a VARCHAR value. Here is an example query that demonstrates how to convert an XMLType to a VARCHAR: SELECT XMLColumn.getStringVal() AS VARCHARColumn FROM YourTableName; Replace XMLColumn with the name of your XMLType column and YourTableName with the name of your table. This query will return the XML data stored in the XMLType column as a VARCHAR value.
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3 min readTo change the arrow head style in Matplotlib annotate, you can specify the arrowprops parameter when calling the annotate function. Within the arrowprops parameter, you can set the headstyle property to customize the arrow head style. Some available options for arrow head style include '->' for a plain arrow, '<-' for a backwards arrow, 'fancy' for a curved arrow head, and more.
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5 min readTo apply a function to multiple multiindex columns in pandas, you can use the apply function along with axis=1 parameter. If you have a DataFrame with a multiindex column, you can specify the level of the multiindex that you want to apply the function to. This can be achieved by specifying the level parameter when calling the apply function. By specifying level=0 for a multiindex, you can apply the function to the first level of the multiindex columns.
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3 min readTo plot a list of byte data with matplotlib, you can first convert the byte data to numeric values that can be plotted. One way to do this is by using the struct module in Python to unpack the byte data into integers. Once you have converted the byte data to a list of numeric values, you can then use matplotlib to create a plot by calling functions such as plt.plot() or plt.scatter().
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5 min readTo import a CSV file into a remote Oracle database, you can use SQLLoader, Oracle Data Pump, or Oracle SQL Developer. SQLLoader is a command-line tool that loads data from external files into Oracle databases. Oracle Data Pump is a feature of Oracle Database that provides high-speed data transfer for loading and unloading data. Oracle SQL Developer is a graphical tool that allows you to import and export data easily.
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4 min readTo save multiple animations into one in matplotlib, you can create each animation separately and then combine them into a single figure. One way to do this is by creating subplots within a single figure using the add_subplot function. You can then plot each animation on a different subplot and save the entire figure using the savefig function. This allows you to save all the animations into one file for easy access and sharing.