sqlite insert or update overwriting primary key

Since they are produced by calculations, these columns can not be inserted into directly.ĭuckDB can infer the type of the generated column based on the expression’s return type. The data in this kind of column is generated from its expression, which can reference other (regular or generated) columns of the table. The AS (expr) syntax will create a generated column.

Temporary tables reside in memory rather than on disk (even when connecting to a persistent DuckDB), but if the temp_directory configuration is set when connecting or with a SET command, data will be spilled to disk if memory becomes constrained.ĬREATE TABLE t5 ( id INTEGER UNIQUE, j VARCHAR ) CREATE TABLE t6 ( id INTEGER PRIMARY KEY, t5_id INTEGER, FOREIGN KEY ( t5_id ) REFERENCES t5 ( id ) ) įoreign keys with cascading deletes ( FOREIGN KEY. Temporary tables are session scoped (similar to PostgreSQL for example), meaning that only the specific connection that created them can access them, and once the connection to DuckDB is closed they will be automatically dropped. Temporary tables can be created using the CREATE TEMP TABLE or the CREATE TEMPORARY TABLE statement (see diagram below). create a table with two integer columns (i and j) CREATE TABLE t1 ( i INTEGER, j INTEGER ) - create a table with a primary key CREATE TABLE t1 ( id INTEGER PRIMARY KEY, j VARCHAR ) - create a table with a composite primary key CREATE TABLE t1 ( id INTEGER, j VARCHAR, PRIMARY KEY ( id, j )) - create a table with various different types and constraints CREATE TABLE t1 ( i INTEGER NOT NULL, decimalnr DOUBLE CHECK ( decimalnr < 10 ), date DATE UNIQUE, time TIMESTAMP ) - create table as select (CTAS) CREATE TABLE t1 AS SELECT 42 AS i, 84 AS j - create a table from a CSV file (automatically detecting column names and types) CREATE TABLE t1 AS SELECT * FROM read_csv ( 'path/file.csv' ) - we can use the FROM-first syntax to omit 'SELECT *' CREATE TABLE t1 AS FROM read_csv ( 'path/file.csv' ) - copy the schema of t2 to t1 CREATE TABLE t1 AS FROM t2 LIMIT 0 Temporary Tables

Sqlite insert or update overwriting primary key