由于columns_list被明确指定,因此在导入时不会出现数据被导入到错误字段的问题。 --inserts 导出的数据用insert命令表示,而不是copy命令。即便使用insert要比copy慢一些,但是对于今后导入到其他非PostgreSQL的数据库是比较有意义的。 --no-tablespaces 不输出设置表空间的命令,如果带有这个选项
Individual fields will * have been evaluated into columns of the tuple deformed by the preceding * DEFORM step. */ EEOP_FIELDSTORE_FORM, /* Process container subscripts; possibly short-circuit result to NULL */ EEOP_SBSREF_SUBSCRIPTS, /* * Compute old container element/slice when a ...
By default, for the planner there is no relationship between f1 and f2 columns. However, in this case the value of f1 is sufficient to determine the value of f2; and there are no two rows having the same value of f1 but different values of f2. Let us create a statistics object to ...
::: [C201901140001] <== Columns: id, commodity_code, name, count <== Row: 1, C201901140001, 水杯, 650 <== Total: 1 Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@48378073] Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@48378073]...
Improved CTE plans by considering the statistics and sort order of columns referenced in earlier row output clauses Allow pushdown of EXISTS and IN subqueries to the postgres_fdw foreign server EXPLAIN (VERBOSE, COSTS OFF) SELECT t1.c1 FROM ft1 t1 WHERE EXISTS (SELECT 1 FROM ft2 t2 WHERE ...
4 Postgres order by with multiple columns 1 Why is the default collation not applied in PostgreSQL queries? 1 Why is Postgres so slow to order those 200 rows that are already ordered? 3 Managing the order of aggregation in Postgres Hot Network Questions What song about a little...
By default, all columns are replicated. BDR replicates data columns based on the column name. If a column has the same name but a different datatype, we attempt to cast from the source type to the target type, if casts were defined that allow that. ...
DEFAULT- records the old values of the columns of the primary key, if any (this is the default PostgreSQL behavior). FULL- records the old values of all columns in the row. NOTHING- records no information about the old row. SeePostgreSQL documentationfor more details. ...
Incremental sortswere first added in PostgreSQL 13. These incremental sorts reduce the effort required to get sorted results. How? By exploiting the knowledge that some given result set is already sorted by 1 or more leading columns—and only performing a sort on the remaining ...
How to Index JSONB Columns in PostgreSQLHow to Monitor and Optimize PostgreSQL Index PerformancePostgreSQL Performance Tuning: Optimizing Database IndexesOptimizing Array Queries With GIN Indexes in PostgreSQLSQL/JSON Data Model and JSON in SQL: A PostgreSQL PerspectiveHow to Query JSON Metadata in Post...