CreateIndex is used to create indexes in tables. Indexes are used to speed up searches/queries. This method may needs some privilege according to the database product and its version.
PRIMARY KEY cannot be created independent from a table, it can only created during table creation or deletion. Examples Following section demonstrates how to create index for a table.

        {{hl}}var ddl = connection.DDL();{{/hl}}

		// by table alias
		var t0 = new Orders().AsQueryable();
		ddl.{{hl}}CreateIndex{{/hl}}(t0, t0.Indexes.First(), "my_index");

		// by table name
		ddl.{{hl}}CreateIndex{{/hl}}("table1", true, new[] { "column1", "column2" }, "my_index");

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