merge pandas

1pd.merge(df1, df2, left_index=True, right_index=True)
2

1df_3 = pd.concat([df_1, df_2])
2

1df.merge(df2, left_on = "doc_id", right_on = "doc_num", how = "left")

1select * from bricks, colours;
2
3

1select * from bricks;
2
3select * from colours;

1create table bricks (
2  brick_id integer,
3  colour   varchar2(10)
4);
5
6create table colours (
7  colour_name           varchar2(10),
8  minimum_bricks_needed integer
9);
10
11insert into colours values ( 'blue', 2 );
12insert into colours values ( 'green', 3 );
13insert into colours values ( 'red', 2 );
14insert into colours values ( 'orange', 1);
15insert into colours values ( 'yellow', 1 );
16insert into colours values ( 'purple', 1 );
17
18insert into bricks values ( 1, 'blue' );
19insert into bricks values ( 2, 'blue' );
20insert into bricks values ( 3, 'blue' );
21insert into bricks values ( 4, 'green' );
22insert into bricks values ( 5, 'green' );
23insert into bricks values ( 6, 'red' );
24insert into bricks values ( 7, 'red' );
25insert into bricks values ( 8, 'red' );
26insert into bricks values ( 9, null );
27
28commit;