Das Sparschwein steht als Trinkgelddose auf dem Tisch.

Because Sparschwein is a neuter noun in German, so it takes the article das in the nominative singular: das Sparschwein.

A useful thing to know is that German nouns have grammatical gender, and that gender does not always match biological sex or English logic. A Sparschwein is a pig-shaped money box, and its grammatical gender just happens to be neuter.

So:

• das Sparschwein = the piggy bank

If you used der or die, it would simply be the wrong article for this noun.

Not usually in this sentence. Sparschwein is a common German word for a piggy bank.

It is made from:

• sparen = to save
• Schwein = pig

So literally it is something like saving pig, but in normal English you would say piggy bank.

In this sentence, it refers to an object, not a real animal.

Because German very often forms nouns by combining smaller words into a single compound noun.

Here:

• Trinkgeld = tip / gratuity
• Dose = can, tin, container

So:

• Trinkgelddose = tip jar / container for tips

This is very normal in German. English often writes similar ideas as multiple words, but German prefers one combined noun.

The last part usually determines the basic category:

• a Dose is a container
• so a Trinkgelddose is a kind of container

Because after als in this sentence, German often uses a noun without an article when it describes a role, function, or status.

So:

• als Trinkgelddose = as a tip jar

This is similar to:

• Er arbeitet als Lehrer. = He works as a teacher.
• Sie benutzt die Schüssel als Salatschüssel. = She uses the bowl as a salad bowl.

The noun after als is not being introduced as a specific separate object with its own article. It is describing what the piggy bank is functioning as.

Here als means as.

So:

• als Trinkgelddose = as a tip jar

It shows the role or function of the object. The piggy bank is being used as a tip jar.

This is different from other uses of als, such as:

• größer als = bigger than

In your sentence, it is the role/function use of als.

German often uses position verbs more specifically than English does.

• stehen = to stand
• liegen = to lie
• sitzen = to sit
• sein = to be

For objects that are upright or placed in a standing position, German often says stehen, even when English might just say is.

So:

• Das Sparschwein steht auf dem Tisch. = The piggy bank is standing/on the table. = more natural English: The piggy bank is on the table.

German prefers steht here because it describes the physical position of the object.

Because auf is a two-way preposition, and the case depends on whether there is:

• location → dative
• movement toward a destination → accusative

Here the sentence describes where the piggy bank is located:

• auf dem Tisch = on the table

So German uses the dative:

• dem Tisch

Compare:

• Das Sparschwein steht auf dem Tisch. = The piggy bank is on the table.
  → location, so dative
• Ich stelle das Sparschwein auf den Tisch. = I put the piggy bank onto the table.
  → movement to a destination, so accusative

That is why dem is correct here.

Because Tisch is a masculine noun, and after auf with a location meaning, German uses the dative case.

The masculine article changes like this:

• nominative: der Tisch
• dative: dem Tisch

So:

• auf dem Tisch = on the table

This is a standard case change, not a special property of Tisch itself.

The structure is:

• Das Sparschwein = subject
• steht = verb
• als Trinkgelddose = role/function phrase
• auf dem Tisch = location

So the sentence follows normal German main-clause word order:

1. something in the first position
2. the conjugated verb in the second position
3. the rest of the sentence

Here that gives:

• Das Sparschwein steht als Trinkgelddose auf dem Tisch.

This is very standard German word order.

Grammatically, you might understand it, but it is less natural in this context.

German usually prefers steht for an upright object placed somewhere. Using ist is more general and less vivid.

So:

• steht auf dem Tisch sounds natural
• ist auf dem Tisch is possible in some contexts, but less idiomatic if the object’s position is clearly one of standing

German often chooses a positional verb where English would simply use is.

It usually describes the function here: what it is being used as.

A Sparschwein is normally a piggy bank, but in this situation it is serving as a tip jar.

So the sentence suggests:

• the object is a piggy bank
• but in this context, it functions as a container for tips

That is exactly the kind of idea als + noun often expresses.

Yes, it can. German word order is flexible with these kinds of phrases, especially after the verb.

For example:

• Das Sparschwein steht auf dem Tisch als Trinkgelddose.

This is possible, but many speakers may prefer:

• Das Sparschwein steht als Trinkgelddose auf dem Tisch.

Putting als Trinkgelddose earlier can make the function feel more closely connected to Sparschwein. Putting auf dem Tisch earlier can make the location feel more prominent.

So the original sentence is natural, but other orders may also work depending on emphasis.