You can examine your node's database using HSQLDB's "sqltool". It's a good idea to install "rlwrap" (ReadLine wrapper) too as sqltool doesn't support command history/editing.
Typical command line for sqltool would be:
rlwrap java -cp ${HSQLDB_JAR}:${SQLTOOL_JAR} org.hsqldb.cmdline.SqlTool --rcFile=${SQLTOOL_RC} qortal
${HSQLDB_JAR} should be set with pathname where Maven downloaded hsqldb,
typically ${HOME}/.m2/repository/org/hsqldb/hsqldb/2.5.1/hsqldb-2.5.1.jar
${SQLTOOL_JAR} should be set with pathname where Maven downloaded sqltool,
typically ${HOME}/.m2/repository/org/hsqldb/sqltool/2.5.0/sqltool-2.5.0.jar
${SQLTOOL_RC} should be set with pathname of a text file describing HSQLDB databases,
e.g. ${HOME}/.sqltool.rc, with contents like:
urlid qortal
url jdbc:hsqldb:file:db/blockchain
username SA
password
Above url component file:db/blockchain assumes you will call sqltool from directory containing db/.
Another idea is to assign a shell alias in your .bashrc like:
export HSQLDB_JAR=${HOME}/.m2/repository/org/hsqldb/hsqldb/2.5.1/hsqldb-2.5.1.jar
export SQLTOOL_JAR=${HOME}/.m2/repository/org/hsqldb/sqltool/2.5.0/sqltool-2.5.0.jar
alias sqltool='rlwrap java -cp ${HSQLDB_JAR}:${SQLTOOL_JAR} org.hsqldb.cmdline.SqlTool --rcFile=${SQLTOOL_RC}'
So you can simply type: sqltool qortal
Don't forget to use SHUTDOWN; before exiting sqltool so that database files are closed cleanly.
With sqltool-2.5.0.jar and qortal.jar in current directory, and database in db/
java -cp qortal.jar:sqltool-2.5.0.jar org.hsqldb.cmdline.SqlTool --inlineRc=url=jdbc:hsqldb:file:db/blockchain