( lz4 is available only if -with-lz4 was used when building PostgreSQL. The supported compression methods are pglz and lz4. (See ALTER TABLE for information on column storage modes.) Setting this property for a partitioned table has no direct effect, because such tables have no storage of their own, but the configured value will be inherited by newly-created partitions. Compression is supported only for variable-width data types, and is used only when the column's storage mode is main or extended. The COMPRESSION clause sets the compression method for the column. Query tool does not want to create a table in PostgreSQL. Use of EXTERNAL will make substring operations on very large text and bytea values run faster, at the penalty of increased storage space. EXTENDED is the default for most data types that support non- PLAIN storage. Writing DEFAULT sets the storage mode to the default mode for the column's data type. By default, the starting value for AUTOINCREMENT is 1, and it will increment by 1 for each new record. In such cases, PostgreSQL will address all behind the scene complexities and auto-increment the primary key value for each insertion. The following SQL statement defines the 'Personid' column to be an auto-increment primary key field in the 'Persons' table: MySQL uses the AUTOINCREMENT keyword to perform an auto-increment feature. ![]() ![]() EXTERNAL is for external, uncompressed data, and EXTENDED is for external, compressed data. To define an auto-incremented primary key in Postgres, specify a column name followed by a pseudo data type named SERIAL, and then specify the PRIMARY KEY keyword. PLAIN must be used for fixed-length values such as integer and is inline, uncompressed. This controls whether this column is held inline or in a secondary TOAST table, and whether the data should be compressed or not. This form sets the storage mode for the column. In fact, you don't even need autoincrementTrue or db.Sequence('seqregid', start1, increment1), as SQLAlchemy will automatically set the first Integer PK column that's not marked as a FK as autoincrementTrue.
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