Examples of SQL parsing

Simple SQL parsing

Statement stmt = CCJSqlParserUtil.parse("SELECT * FROM tab1");

Starting from stmt you can dive into the parsing result.

SQL script parsing

Statements stmt = CCJSqlParserUtil.parseStatements("SELECT * FROM tab1; SELECT * FROM tab2");

Starting from stmt you can use the parsing result.

Simple Expression parsing

Expression expr = CCJSqlParserUtil.parseExpression("a*(5+mycolumn)");

Starting from expr you can use the parsing result.

Extract table names from SQL

Statement statement = CCJSqlParserUtil.parse("SELECT * FROM MY_TABLE1");
Select selectStatement = (Select) statement;
TablesNamesFinder tablesNamesFinder = new TablesNamesFinder();
List<String> tableList = tablesNamesFinder.getTableList(selectStatement);

In tableList are all table names of the parsed SQL statement. The table names finder is an example of JSqlParser visitor pattern structure. You can use the visitor pattern to traverse the parsing result and compute on it.

Apply aliases to all expressions

Select select = (Select) CCJSqlParserUtil.parse("select a,b,c from test");
final AddAliasesVisitor instance = new AddAliasesVisitor();
select.getSelectBody().accept(instance);

As a result you will get SELECT a AS A1, b AS A2, c AS A3 FROM test. At the moment the prefix can be configured.

Add a column or expression to a select

Select select = (Select) CCJSqlParserUtil.parse("select a from mytable");
SelectUtils.addExpression(select, new Column("b"));

Now select contains SELECT a, b FROM mytable.