eugene 0.8.3

Careful with That Lock, Eugene
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178

## ✅ Eugene trace report

Script name: `examples/E5/good/1.sql`


### ✅ Statement number 1 for 10ms

```sql
-- 1.sql
create table prices (
    id integer generated always as identity
        primary key,
    price int not null
)
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

No new locks taken by this statement.


## ✅ Eugene trace report

Script name: `examples/E5/good/2.sql`


### ✅ Statement number 1 for 10ms

```sql
-- 2.sql
set local lock_timeout = '2s'
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

No new locks taken by this statement.


### ✅ Statement number 2 for 10ms

```sql
alter table prices
    add column new_price bigint
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

| Schema | Object | Mode | Relkind | OID | Safe | Duration held (ms) |
|--------|--------|------|---------|-----|------|--------------------|
| `public` | `prices` | `AccessExclusiveLock` | Table | 1 | ❌ | 10 |


## ✅ Eugene trace report

Script name: `examples/E5/good/3.sql`


### ✅ Statement number 1 for 10ms

```sql
-- 3.sql
update prices set new_price = price :: bigint
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

No new locks taken by this statement.


### ✅ Statement number 2 for 10ms

```sql
set local lock_timeout = '2s'
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

No new locks taken by this statement.


### ✅ Statement number 3 for 10ms

```sql
alter table prices
    add constraint check_new_price_not_null
        check (new_price is not null) not valid
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

| Schema | Object | Mode | Relkind | OID | Safe | Duration held (ms) |
|--------|--------|------|---------|-----|------|--------------------|
| `public` | `prices` | `AccessExclusiveLock` | Table | 1 | ❌ | 10 |


## ✅ Eugene trace report

Script name: `examples/E5/good/4.sql`


### ✅ Statement number 1 for 10ms

```sql
-- 4.sql
set local lock_timeout = '2s'
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

No new locks taken by this statement.


### ✅ Statement number 2 for 10ms

```sql
alter table prices
    validate constraint check_new_price_not_null,
    drop column price
```

#### Locks at start

No locks held at the start of this statement.

#### New locks taken

| Schema | Object | Mode | Relkind | OID | Safe | Duration held (ms) |
|--------|--------|------|---------|-----|------|--------------------|
| `public` | `prices` | `AccessExclusiveLock` | Table | 1 | ❌ | 10 |


### ✅ Statement number 3 for 10ms

```sql
-- eugene: ignore E4
-- this has to run in the same transaction as dropping the old price column
alter table prices
    rename column new_price to price
```

#### Locks at start

| Schema | Object | Mode | Relkind | OID | Safe | Duration held (ms) |
|--------|--------|------|---------|-----|------|--------------------|
| `public` | `prices` | `AccessExclusiveLock` | Table | 1 | ❌ | 10 |

#### New locks taken

No new locks taken by this statement.