integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions • index methods tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating sys- tems form an example of | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions 1 https://dsf tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating systems form an example of a | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions • index methods tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating sys- tems form an example of | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions 1 https://dsf tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating systems form an example of a | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions • index methods tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating sys- tems form an example of | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions 1 https://dsf tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating systems form an example of a | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions • index methods tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating sys- tems form an example of | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions 1 https://dsf tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating systems form an example of a | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types 1. https://dsf.berkeley.edu/postgres.html xlvi Preface tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating systems form an example of a | 1 | 5000 | 4866.6666666666666667 sales | 4 | 4800 | 4866.6666666666666667 (10 rows) The first three output columns come directly from the table empsalary, and there is one output row for each row in

integrity • multiversion concurrency control Also, PostgreSQL can be extended by the user in many ways, for example by adding new • data types • functions • operators • aggregate functions • index tables is so commonplace today that it might seem inherently obvious, but there are a number of other ways of organizing databases. Files and directories on Unix-like operating systems form an example of a to determine which rows will be inputs to the aggregates. On the other hand, the HAVING clause al- ways contains aggregate functions. (Strictly speaking, you are allowed to write a HAVING clause that doesn’t