( 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. I am trying to auto increment a table with a single column which is a primary key, eg: CREATE TABLE mytable (id PRIMARY KEY NOT NULL) I would usually just not include the primary key column in the insert statment in order to autoincrement it, but this doesn't seem possible in the case where there is only a single column. ![]() Compression is supported only for variable-width data types, and is used only when the column's storage mode is main or extended. create or replace function autoid () returns varchar as select 'SO'nextval ('seqautoid') language sql. Create A Function to generate alpha numeric id. The COMPRESSION clause sets the compression method for the column. CREATE SEQUENCE seqautoid INCREMENT 1 MINVALUE 1 MAXVALUE 9223372036854775807 START 10000. 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. EXTERNAL is for external, uncompressed data, and EXTENDED is for external, compressed data. PLAIN must be used for fixed-length values such as integer and is inline, uncompressed. By default, the starting value for AUTOINCREMENT is 1, and it will increment by 1 for each new record. ![]() This controls whether this column is held inline or in a secondary TOAST table, and whether the data should be compressed or not. 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. ![]() This form sets the storage mode for the column.
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