multiple threads • A motivating problem • Some possible solutions • A solution based on strict timestamp ordering (STO) • Testing the STO-based solution ## • Summary ## Sharing a Container ## • Sometimes Another Solution – Strict Timestamp Ordering (STO) ## • STO is one of many database concurrency control algorithms • It is a transactional, timestamp-based algorithm ## • Timestamp • A monotonically increasing value that indicates the age of a transaction • A lower timestamp value (TSV) indicates an older transaction • A higher timestamp value indicates a newer transaction • A transaction's TSV

the standard SQL types int, small int, real, double precision, char (N), varchar (N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

1090 36.4. Valid Input Formats for rdefmtdate ..... 1091 36.5. Valid Input Formats for PGTYPE$timestamp_from_asc ..... 1092 37.1. information_schema_catalog_name Columns ..... 1176 37.2. administ the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single

the standard SQL types int, smallint, real, double precision, char(N), varchar(N), date, time, timestamp, and interval, as well as other types of general utility and a rich set of geometric types. PostgreSQL SELECT DISTINCT city FROM weather; city Hayward San Francisco (2 rows) Here again, the result row ordering might vary. You can ensure consistent results by using DISTINCT and ORDER BY together: $ ^{2} $ collection of rows defined by this virtual table. We already saw that ORDER BY can be omitted if the ordering of rows is not important. It is also possible to omit PARTITION BY, in which case there is a single