137 lines
4.1 KiB
Markdown
137 lines
4.1 KiB
Markdown
|
|
|
|
INSERT statement is used to insert a single record or multiple records
|
|
into a table. More about PostgreSQL INSERT statement can be found here: https://www.postgresql.org/docs/11/sql-insert.html
|
|
|
|
Following clauses are supported:
|
|
- INSERT(columns...) - list of columns for insert
|
|
- VALUES(values...) - list of values
|
|
- MODEL(model) - list of values for columns will be extracted from model object
|
|
- MODELS([]model) - list of values for columns will be extracted from list of model objects
|
|
- QUERY(select) - select statement that supplies the rows to be inserted.
|
|
- RETURNING(output_expression...) - An expressions to be computed and returned by the INSERT statement after each row is inserted.
|
|
The expressions can use any column names of the table. Write _TableName_.AllColumns to return all columns.
|
|
|
|
|
|
_This list might be extended with feature Jet releases._
|
|
|
|
|
|
## Example
|
|
### Insert row by row
|
|
|
|
```
|
|
insertStmt := Link.INSERT(Link.ID, Link.URL, Link.Name, Link.Description).
|
|
VALUES(100, "http://www.postgresqltutorial.com", "PostgreSQL Tutorial", DEFAULT).
|
|
VALUES(101, "http://www.google.com", "Google", DEFAULT).
|
|
VALUES(102, "http://www.yahoo.com", "Yahoo", nil)
|
|
```
|
|
Debug SQL of above insert statement:
|
|
|
|
```sql
|
|
INSERT INTO test_sample.link (id, url, name, description) VALUES
|
|
(100, 'http://www.postgresqltutorial.com', 'PostgreSQL Tutorial', DEFAULT),
|
|
(101, 'http://www.google.com', 'Google', DEFAULT),
|
|
(102, 'http://www.yahoo.com', 'Yahoo', NULL)
|
|
```
|
|
|
|
|
|
|
|
There is also shorthand notation for inserting model data:
|
|
```
|
|
tutorial := model.Link{
|
|
ID: 100,
|
|
URL: "http://www.postgresqltutorial.com",
|
|
Name: "PostgreSQL Tutorial",
|
|
}
|
|
|
|
google := model.Link{
|
|
ID: 101,
|
|
URL: "http://www.google.com",
|
|
Name: "Google",
|
|
}
|
|
|
|
yahoo := model.Link{
|
|
ID: 102,
|
|
URL: "http://www.yahoo.com",
|
|
Name: "Yahoo",
|
|
}
|
|
|
|
insertStmt := Link.INSERT(Link.ID, Link.URL, Link.Name, Link.Description).
|
|
MODEL(turorial).
|
|
MODEL(google).
|
|
MODEL(yahoo)
|
|
```
|
|
Or event shorter if model data is in the slice:
|
|
```
|
|
insertStmt := Link.INSERT(Link.ID, Link.URL, Link.Name, Link.Description).
|
|
MODELS([]model.Link{turorial, google, yahoo})
|
|
```
|
|
`Link.ID, Link.URL, Link.Name, Link.Description` - is the same as Link.AllColumns
|
|
so above statement can be simplified to:
|
|
|
|
```
|
|
insertStmt := Link.INSERT(Link.AllColumns).
|
|
MODELS([]model.Link{turorial, google, yahoo})
|
|
```
|
|
|
|
`Link.ID` is a primary key autoincrement column so it can be omitted in INSERT statement.
|
|
`Link.MutableColumns` - is shorthand notation for list of all columns minus primary key columns.
|
|
|
|
```
|
|
insertStmt := Link.INSERT(Link.MutableColumns).
|
|
MODELS([]model.Link{turorial, google, yahoo})
|
|
```
|
|
|
|
Inserts using `VALUES`, `MODEL` and `MODELS` can appear as the part of the same insert statement.
|
|
|
|
```
|
|
insertStmt := Link.INSERT(Link.ID, Link.URL, Link.Name, Link.Description, Link.Description).
|
|
VALUES(101, "http://www.google.com", "Google", DEFAULT, DEFAULT).
|
|
MODEL(turorial).
|
|
MODELS([]model.Link{yahoo})
|
|
```
|
|
|
|
### Insert using query
|
|
```
|
|
// duplicate first 10 entries
|
|
insertStmt := Link.
|
|
INSERT(Link.URL, Link.Name).
|
|
QUERY(
|
|
SELECT(Link.URL, Link.Name).
|
|
FROM(Link).
|
|
WHERE(Link.ID.GT(Int(0)).AND(Link.ID.LT_EQ(10))),
|
|
)
|
|
```
|
|
|
|
## Execute statement
|
|
|
|
To execute insert statement and get sql.Result:
|
|
|
|
```
|
|
res, err := insertStmt.Exec(db)
|
|
```
|
|
|
|
To execute insert statement and return row records inserted, insert statement has to have RETURNING clause:
|
|
```
|
|
insertStmt := Link.INSERT(Link.ID, Link.URL, Link.Name, Link.Description).
|
|
VALUES(100, "http://www.postgresqltutorial.com", "PostgreSQL Tutorial", DEFAULT).
|
|
VALUES(101, "http://www.google.com", "Google", DEFAULT).
|
|
RETURNING(Link.ID, Link.URL, Link.Name, Link.Description) // or RETURNING(Link.AllColumns)
|
|
|
|
dest := []model.Link{}
|
|
|
|
err := insertStmt.Query(db, &dest)
|
|
```
|
|
|
|
Use `ExecContext` and `QueryContext` to provide context object to execution.
|
|
|
|
##### SQL table used for the example:
|
|
```sql
|
|
CREATE TABLE IF NOT EXISTS link (
|
|
id serial PRIMARY KEY,
|
|
url VARCHAR (255) NOT NULL,
|
|
name VARCHAR (255) NOT NULL,
|
|
description VARCHAR (255)
|
|
);
|
|
```
|
|
|