@@ -14,6 +14,22 @@ TutorialD (master/main):
1414
1515"master" refers to the name of the branch to which the current transaction will be potentially committing.
1616
17+### Date's Sample Relations
18+
19+The examples in this tutorial can be executed after loading Chris Date's sample relations using:
20+
21+```
22+:importexample date
23+```
24+
25+Each section assumes a fresh instance of the Date examples. The relation variables created in the script are:
26+
27+|Relation Variable Name|Description|
28+|----------------------|-----------|
29+|s|suppliers|
30+|p|parts|
31+|sp|contains mapping of which suppliers supply which parts|
32+
1733### Types
1834
1935TutorialD is strongly-typed. The basic built-in types are:
@@ -37,7 +53,7 @@ The ```interval``` function last two arguments are boolean values indicating whe
3753Project:M36 will complain loudly if the expected types do not match. Automatic type coercion does not exist.
3854
3955```
40−TutorialD (master/main): :showexpr S:{more:=add(10,@sname)}
56+TutorialD (master/main): :showexpr s:{more:=add(10,@sname)}
4157ERR: AtomFunctionTypeError "add" 2 IntAtomType StringAtomType
4258```
4359
@@ -68,22 +84,6 @@ Chris Date refers to these relations as "TABLE_DUM" and "TABLE_DEE" but such arb
6884products{}
6985```
7086
71−### Date's Sample Relations
72−
73−The examples in this tutorial can be executed after loading Chris Date's sample relations using:
74−
75−```
76−:importexample date
77−```
78−
79−Each section assumes a fresh instance of the Date examples. The relation variables created in the script are:
80−
81−|Relation Variable Name|Description|
82−|----------------------|-----------|
83−|s|suppliers|
84−|p|parts|
85−|sp|contains mapping of which suppliers supply which parts|
86−
8787### Relational Expressions
8888
8989A relational expression combines relational operators to create a new relation. ```tutd``` can display the result of executing a relational expression with ":showexpr".