as shown in the figure, the data I want to take out is in the format of figure 2. How to write the sql statement, only take out market_value and timestamp_day
as shown in the figure, the data I want to take out is in the format of figure 2. How to write the sql statement, only take out market_value and timestamp_day
first fetch the corresponding column data with sql. select market_value,timestamp_day from table_name
takes out an array of objects, and then converts it into a two-dimensional array
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