db: updating from staging

cst363/lec/lec8.md

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+# lec8
+
+## Lab
+
+The lab exercises for this lecture can found under `lab/` as `db-mods-transactions-lab.pdf`.
+
+
+DB Modifications, plus transactions
+
+## Modifyinig Data
+
+Since we're dealing with data we may need to add, delete or modify entries in some table.
+
+When we have inserted data before we have done simple insertions like in the previous lab exercises `insert into tableName values(...);`.
+Where the arguments are listed in the same order as they are listed in the table structure.
+
+However, we can pass arguments by name, elminating the need to provide them in a rigid order: 
+```
+insert into tableName(list, of, attributes) values('respective', 'data', 'entries');
+```
+
+We can also move things from one table into another table.
+```
+insert into targetTable select ... from hostTable;
+```
+
+### Deleting
+
+```
+delete from tableName where ...;
+```
+
+Deletes a _whole row_.
+Caution: the delete operation also accepts tables as valid arguments so a query that returns multiple rows as a table will be deleted in the `targetTable` mentioned earlier.
+
+### Updating entries
+
+```
+update tableName set attribute=123 where def='abc';
+```
+
+The above updates an attribute based on the condiftion `where def='abc'`.
+
+## Transactions
+
+Set of instructions which upon failure do not modify any state.
+
+```
+begin;
+	// set of commands
+	// wew
+end;
+```
+
+## Inner/Outer Joins
+
+> left (left outer)
+
+_the outer part is implied so it's unnecessary to write it in_
+