Insert Or Update

1. IFreeSql.InsertOrUpdate

IFreeSql defines the InsertOrUpdate method, which uses the characteristics and functions of the database to implement the added or modified functions. (since 1.5.0)

Database	Features		Database	Features
MySql	on duplicate key update		Dameng	merge into
PostgreSQL	on conflict do update		Kingbase ES	on conflict do update
SqlServer	merge into		Shentong Database	merge into
Oracle	merge into		MsAccess	not support
Sqlite	replace into
Firebird	merge into

fsql.InsertOrUpdate<T>()
  .SetSource(items) //Data to be processed
  //.IfExistsDoNothing() //If the data exists, do nothing (that means, insert the data if and only if the data does not exist)
  .ExecuteAffrows();

When the entity class has auto-increment properties, batch InsertOrUpdate can be split into two executions at most. Internally, FreeSql will calculate the data without self-increment and with self-increment, and execute the two commands of insert into and merge into mentioned above (using transaction execution).

Note: the common repository in FreeSql.Repository also has InsertOrUpdate method, but their mechanism is different.

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2. InsertOrUpdate in FreeSql.Repository

To use this method, you need to reference the FreeSql.Repository or FreeSql.DbContext extensions package.

var repo = fsql.GetRepository<T>();
repo.InsertOrUpdate(YOUR_ENTITY);

If there is data in the internal state management, then update it.

If there is no data in the internal state management, query the database to determine whether it exists.

Update if it exists, insert if it doesn't exist

Disadvantages: does not support batch operations

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3. Batch Editing: BeginEdit

[Fact]
public void BeginEdit()
{
    fsql.Delete<BeginEdit01>().Where("1=1").ExecuteAffrows();
    var repo = fsql.GetRepository<BeginEdit01>();
    var cts = new[] {
        new BeginEdit01 { Name = "Category1" },
        new BeginEdit01 { Name = "Category1_1" },
        new BeginEdit01 { Name = "Category1_2" },
        new BeginEdit01 { Name = "Category1_3" },
        new BeginEdit01 { Name = "Category2" },
        new BeginEdit01 { Name = "Category2_1" },
        new BeginEdit01 { Name = "Category2_2" }
    }.ToList();
    repo.Insert(cts);

    repo.BeginEdit(cts); //Start editing `cts`

    cts.Add(new BeginEdit01 { Name = "Category2_3" });
    cts[0].Name = "123123";
    cts.RemoveAt(1);

    Assert.Equal(3, repo.EndEdit());
}
class BeginEdit01
{
    public Guid Id { get; set; }
    public string Name { get; set; }
}

When the above code EndEdit method is executed, 3 SQL statements are generated, as follows:

INSERT INTO "BeginEdit01"("Id", "Name") VALUES('5f26bf07-6ac3-cbe8-00da-7dd74818c3a6', 'Category2_3')


UPDATE "BeginEdit01" SET "Name" = '123123' 
WHERE ("Id" = '5f26bf00-6ac3-cbe8-00da-7dd01be76e26')


DELETE FROM "BeginEdit01" WHERE ("Id" = '5f26bf00-6ac3-cbe8-00da-7dd11bcf54dc')

Use case: In winform, after loading the table data, perform some operations such as adding, modifying, and deleting, and then click [Save]

Note: This operation is only valid for the variable cts, not for comparison and update of the entire table.

4. On Duplicate Key Update (MySql only)

FreeSql.Provider.MySql and FreeSql.Provider.MySqlConnector support MySql's unique function On Duplicate Key Update.

This function can also insert or update data, and supports batch operations.

class TestOnDuplicateKeyUpdateInfo {
    [Column(IsIdentity = true)]
    public int id { get; set; }
    public string title { get; set; }
    public DateTime time { get; set; }
}

var item = new TestOnDuplicateKeyUpdateInfo { id = 100, title = "title-100", time = DateTime.Parse("2000-01-01") };
fsql.Insert(item)
    .NoneParameter()
    .OnDuplicateKeyUpdate().ToSql();
//INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`, `time`) VALUES(100, 'title-100', '2000-01-01 00:00:00.000')
//ON DUPLICATE KEY UPDATE
//`title` = VALUES(`title`), 
//`time` = VALUES(`time`)

Methods that can be called after OnDuplicateKeyUpdate():

Method	Description
IgnoreColumns	Ignore updated columns, the mechanism is the same as IUpdate.IgnoreColumns
UpdateColumns	Specify updated columns, the mechanism is the same as IUpdate.UpdateColumns
Set	Manually specify the updated column, the same function as IUpdate.Set
SetRaw	As a supplement to the Set method, SQL strings can be passed in.
ToSql	Return the SQL statement to be executed
ExecuteAffrows	Execute and return the number of rows affected

Both IInsert and OnDuplicateKeyUpdate have IgnoreColumns and UpdateColumns methods.

When inserting an entity or a set of entities, the time column is ignored, the code is as follows:

fsql.Insert(item)
    .IgnoreColumns(a => a.time)
    .NoneParameter()
    .OnDuplicateKeyUpdate().ToSql();
//INSERT INTO `TestOnDuplicateKeyUpdateInfo`(`id`, `title`) VALUES(200, 'title-200')
//ON DUPLICATE KEY UPDATE
//`title` = VALUES(`title`), 
//`time` = '2000-01-01 00:00:00.000'

We found that the UPDATE time part became a constant instead of VALUES(`time`). The mechanism is as follows:

When there are columns in the insert part, they will be set in the form of VALUES(`field`) in the update;

When a column that does not exist in the insert part, it will be set as a constant in the update. When manipulating the entity array, this constant is executed for case when ... end (same as IUpdate);

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5. On Conflict Do Update (PostgreSQL only)

FreeSql.Provider.PostgreSQL supports PostgreSQL 9.5+ unique function On Conflict(id) Do Update.

The usage method is roughly the same as that of MySql's OnDuplicateKeyUpdate.

class TestOnConflictDoUpdateInfo {
    [Column(IsIdentity = true)]
    public int id { get; set; }
    public string title { get; set; }
    public DateTime? time { get; set; }
}

var items = new [] {
    new TestOnConflictDoUpdateInfo { id = 200, title = "title-200", time = DateTime.Parse("2000-01-01") },
    new TestOnConflictDoUpdateInfo { id = 201, title = "title-201", time = DateTime.Parse("2000-01-01") },
    new TestOnConflictDoUpdateInfo { id = 202, title = "title-202", time = DateTime.Parse("2000-01-01") }
};
fsql.Insert(items)
    .IgnoreColumns(a => a.time)
    .NoneParameter()
    .OnConflictDoUpdate().ToSql();
//INSERT INTO ""testonconflictdoupdateinfo""(""id"", ""title"") VALUES(200, 'title-200'), (201, 'title-201'), (202, 'title-202')
//ON CONFLICT(""id"") DO UPDATE SET
//""title"" = EXCLUDED.""title"", 
//""time"" = CASE EXCLUDED.""id"" 
//WHEN 200 THEN '2000-01-01 00:00:00.000000' 
//WHEN 201 THEN '2000-01-01 00:00:00.000000' 
//WHEN 202 THEN '2000-01-01 00:00:00.000000' END::timestamp