Add Create A Table From The Structure Of Another as a Postgres TIL

postgres/create-a-table-from-the-structure-of-another.md

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+# Create A Table From The Structure Of Another
+
+There are a couple ways to create a new table from the structure of another table.
+
+One of those ways is with the [`create table as`
+syntax](https://www.postgresql.org/docs/current/sql-createtableas.html).
+
+```sql
+create table dupe_table as table existing_table with no data;
+```
+
+I wouldn't recommend this approach though because it only reproduces the
+columns and datatypes. The modifiers, indexes, and constraints are not
+included.
+
+The [`create table`
+syntax](https://www.postgresql.org/docs/current/sql-createtable.html), on the
+other hand, gives you more options and flexibility for this kind of task.
+
+```sql
+create table dupe_table (like existing_table);
+```
+
+This works just like the first statement, reproducing just the columns and
+datatypes.
+
+There are options for enhancing this statement. We can tell it to additionally
+_include_ things like `defaults`, `indexes`, `constraints`, or even just
+_everything_ (`including all`).
+
+Here is what it looks like to copy the `existing_table` so that things like
+`not null`, B-Tree indexes, and primary key `default` values are reproduced
+along with the columns and datatypes.
+
+```sql
+create table dupe_table (
+  like existing_table
+    including defaults
+    including indexes
+    including constraints
+)
+```
+
+[source](https://www.reddit.com/r/PostgreSQL/comments/uu8xcs/comment/i9e36m2/)