What’s on the SQL Joins poster
A 5-row table: Join · Keeps · Use for.
Which rows survive when there is no matching row on the other side.
- INNER JOIN — Only matching rows — The default; both sides required
- LEFT JOIN — All left, matched right — Optional related data
- RIGHT JOIN — All right, matched left — Rare — flip the tables instead
- FULL OUTER — All rows from both — Reconciling two sources
- CROSS JOIN — Every combination — Deliberate cartesian product
A LEFT JOIN with a condition on the right table in WHERE silently becomes an INNER JOIN. Put it in the ON clause instead.
Questions about the SQL Joins poster
- What’s on the SQL Joins poster?
- A 5-row table: Join · Keeps · Use for. Which rows survive when there is no matching row on the other side. INNER JOIN — Only matching rows — The default; both sides required; LEFT JOIN — All left, matched right — Optional related data; RIGHT JOIN — All right, matched left — Rare — flip the tables instead; FULL OUTER — All rows from both — Reconciling two sources; CROSS JOIN — Every combination — Deliberate cartesian product. A LEFT JOIN with a condition on the right table in WHERE silently becomes an INNER JOIN. Put it in the ON clause instead.
- Who is the SQL Joins poster for?
- SQL Joins belongs to the Computing section rather than to a school year, because computing is not something one grade owns. Anyone learning languages can pin it up — a beginner, a student mid-course, or someone revising years later.
- When should you use the SQL Joins poster?
- Draw the two tables before writing the join. Which side must survive if there is no match? A wall chart earns its place by being glanceable from where the work is happening, so SQL Joins belongs on the wall where that computing work actually happens, within glancing distance, rather than filed away.
- What other posters go with SQL Joins?
- REST API Design, Bash Scripting and Error Handling sit alongside SQL Joins in the Computing section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.REST API DesignBash ScriptingError Handling
- Is the SQL Joins poster free to download and print?
- Yes. SQL Joins downloads as a free PDF with no account, no email and no watermark, like everything else in the Computing section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
- What size does the SQL Joins poster print at?
- SQL Joins is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of SQL Joins loses nothing.Printing guide
Related posters
Charts that sit alongside SQL Joins on the same wall.
Browse every Computing poster, or start from the full catalogue.