Merge Rows
To be able to do a select so as to merge multiple rows into 1 row : "group_concat notation".
MySQL and CUBRID use the group_concat
keyword to achieve that goal, and PostgreSQL 9.0 has the string_agg
function. Versions before 9.0 required the use of something like
or the creation of an aggregate function.
LastName | DepartmentID |
---|---|
Rafferty | 31 |
Jones | 33 |
Steinberg | 33 |
Robinson | 34 |
Smith | 34 |
John | NULL |
DepartmentID | LastNames |
---|---|
NULL | John |
31 | Rafferty |
33 | Jones, Steinberg |
34 | Robinson, Smith |
Read more about this topic: Join (SQL)
Famous quotes containing the words merge and/or rows:
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Gather, and merge myself as part of the sands and drift.”
—Walt Whitman (18191892)
“Over the low, barnacled, elephant-colored rocks,
Come the first tide-ripples, moving, almost without sound, toward
me,
Running along the narrow furrows of the shore, the rows of dead clam shells;”
—Theodore Roethke (19081963)