In this tutorial you have learned how to extract specific columns of a data frame in the R programming language. I have shown in multiple examples how to create subsets of consecutive and non-consecutive variables. If you have comments or questions, please let me know in the comments section ...
Method 1 – Use the Find and Replace Tool to Select Specific Data in Excel Case 1.1 – Using the Keyboard Shortcuts to Select Specific Data in Excel Steps: PressCtrl + F. TheFind & Replacedialog box will appear. In theFind Whattext box, insert the specific data you want to find. Click...
2. In theSelect Specific Cellsdialog box, please configure as follows. 2.1) The selected range is listed in theSelect cells in this rangebox. You can change the range if you need; 2.2) In theSelection typesection, there are three options (in this case, I choose theEntire rowsoption and...
Suppose we want to retrieve specific columns from theemployeestable and rename them in the result set as follows: SELECT employee_id AS emp_id, first_name AS f_name, last_name AS l_name, job_title AS position FROM employees; In the output, we’ll get the following: ...
In Microsoft Excel, the keyboard shortcut "Ctrl + R" serves a specific function: Fill Right: When a cell is selected, pressing "Ctrl + R" copies the content from the cell to the immediate right of the selected cell. This is useful when you want to quickly duplicate the content of a ...
Another popular add-on package for data manipulation is the data.table package. In Example 4, I’ll explain how to use the setDT and J functions to return specific rows of our data. Again, we have to install and load the data.table package first: ...
Specify the object name followed by a period and the asterisk to select all columns from the specified table, view, or materialized view. Oracle Database returns a set of column in the order in which the columns were specified when the object was created. A query that selects rows from tw...
MySQL was able to do aLEFT JOINoptimisation on the query and will not examine more rows in this table for the previous row combination after it finds one row that matches theLEFT JOINcriteria. Here is an example of this: SELECT * FROM t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t2.id ...
SQL_BUFFER_RESULTwill force the result to be put into a temporary table. This will help MySQL free the table locks early and will help in cases where it takes a long time to send the result set to the client. SQL_SMALL_RESULT, a MySQL-specific option, can be used withGROUP BYorDISTI...
('two', 2), ('three', 3), ('four', 4) imagine you want to have one copy of rows alw...