private MyVariableStorage getMyVariableStorage(Address variableAddr) throws IOException {
		if (!variableAddr.isVariableAddress()) {
			throw new IllegalArgumentException("Address is not a VariableAddress: " + variableAddr);
		}
		MyVariableStorage varStore = cache.get(variableAddr.getOffset());
		if (varStore != null) {
			return varStore;
		}
		DBRecord rec = adapter.getRecord(variableAddr.getOffset());
		if (rec == null) {
			return null;
		}
		varStore = new MyVariableStorage(cache, rec);
		cacheMap.put(varStore.getLongHash(), varStore);
		return varStore;
	}
Determine if the variable storage manager table already exists
@param dbHandle database handle
@return true if storage table exists
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/symbol/VariableStorageManagerDB.java