Database
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When creating a crosstab query, where does the value of the column header field appear in the crosstab?
When creating a crosstab query, where does the value of the column header field appear in the crosstab?
When creating a crosstab query, the value of the column header field is displayed in the first row of the crosstab. A crosstab query groups the fields from a table. One group of columns is on the left side of the data table as the row fields of the crosstab, and the other group of columns is on the top of the data table as the column fields of the crosstab.
When creating a crosstab query, the user needs to specify three types of fields:
One is to place it in the data table The leftmost row header, which puts a certain field or related data into a specified row;
The second is the column header placed at the top of the data table, which Perform statistics on the fields or tables specified in each column, and put the statistical results in that column;
The third is the field placed at the intersection of the rows and columns of the data table , the user needs to specify a total item for this field.
Introduction to crosstab query
Crosstab query is to group the fields from a certain table, and a group of columns is listed in the crosstab On the left, a set of columns appears above the crosstab and displays various calculated values for a field in the table where the crosstab rows and columns intersect.
There are two types of crosstabs: static crosstabs and dynamic crosstabs.
Using crosstab queries to calculate and reconstruct data can simplify data analysis. Crosstab queries calculate sums, averages, counts, and other types of statistics on data and group them into one set of columns on the left side of the data table as the row fields of the crosstab, and another set of columns at the top of the data table as the crosstab. column field.
Related recommendations: "mysql tutorial"
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