Package gudusoft.gsqlparser.parser

Class GaussDbSqlParser

Object
gudusoft.gsqlparser.parser.AbstractSqlParser
gudusoft.gsqlparser.parser.GaussDbSqlParser
All Implemented Interfaces:
SqlParser
public class GaussDbSqlParser extends AbstractSqlParser
GaussDB SQL parser implementation.

This parser handles GaussDB-specific SQL syntax including:

  • PostgreSQL-based SQL syntax with Oracle compatibility
  • Stored procedures and functions (Oracle-style and PostgreSQL-style)
  • Package specifications and bodies
  • SQL*Plus-like commands
  • Dynamic delimiter support

Implementation Status: MIGRATED

  • Completed: Migrated from TGSqlParser to AbstractSqlParser
  • Current: Fully self-contained GaussDB parser

Design Notes:

  • Extends AbstractSqlParser using template method pattern
  • Uses single parser: TParserGaussDB
  • Primary delimiter: semicolon (;)
  • Supports both Oracle-style and PostgreSQL-style routines
  • Handles package specifications and bodies with GaussDB-specific state tracking
Since:
3.2.0.0
See Also:

  • Field Details

  • Constructor Details

    • GaussDbSqlParser

      public GaussDbSqlParser()
      Construct GaussDB SQL parser.

      Configures the parser for GaussDB database with semicolon (;) as the default delimiter.

  • Method Details

    • getLexer

      protected TCustomLexer getLexer(ParserContext context)
      Description copied from class: AbstractSqlParser
      Get the lexer for this vendor.

      Subclass Responsibility: Return vendor-specific lexer instance. The lexer may be created fresh or cached/reused for performance.

      Example: 

       protected TCustomLexer getLexer(ParserContext context) {
     TLexerOracle lexer = new TLexerOracle();
     lexer.delimiterchar = delimiterChar;
     lexer.defaultDelimiterStr = defaultDelimiterStr;
     return lexer;
 }
      Specified by:
      getLexer in class AbstractSqlParser
      Parameters:
      context - the parser context
      Returns:
      configured lexer instance (never null)

    • getParser

      protected TCustomParser getParser(ParserContext context, TSourceTokenList tokens)
      Description copied from class: AbstractSqlParser
      Get the main parser for this vendor.

      Subclass Responsibility: Return vendor-specific parser instance. The parser may be created fresh or cached/reused for performance. If reusing, the token list should be updated.

      Example: 

       protected TCustomParser getParser(ParserContext context, TSourceTokenList tokens) {
     TParserOracleSql parser = new TParserOracleSql(tokens);
     parser.lexer = getLexer(context);
     return parser;
 }
      Specified by:
      getParser in class AbstractSqlParser
      Parameters:
      context - the parser context
      tokens - the source token list
      Returns:
      configured parser instance (never null)

    • getSecondaryParser

      protected TCustomParser getSecondaryParser(ParserContext context, TSourceTokenList tokens)
      Description copied from class: AbstractSqlParser
      Get secondary parser (e.g., PL/SQL for Oracle).

      Hook Method: Default implementation returns null. Override if vendor needs a secondary parser. The parser may be created fresh or cached/reused for performance.

      Example (Oracle): 

       protected TCustomParser getSecondaryParser(ParserContext context, TSourceTokenList tokens) {
     TParserOraclePLSql plsqlParser = new TParserOraclePLSql(tokens);
     plsqlParser.lexer = getLexer(context);
     return plsqlParser;
 }
      Overrides:
      getSecondaryParser in class AbstractSqlParser
      Parameters:
      context - the parser context
      tokens - the source token list
      Returns:
      secondary parser instance, or null if not needed

    • tokenizeVendorSql

      protected void tokenizeVendorSql()
      Description copied from class: AbstractSqlParser
      Call vendor-specific tokenization logic.

      Hook Method: Called by AbstractSqlParser.performTokenization(gudusoft.gsqlparser.parser.ParserContext, gudusoft.gsqlparser.TCustomLexer) to execute vendor-specific SQL-to-token conversion logic.

      Subclass Responsibility: Call the vendor-specific tokenization method (e.g., dooraclesqltexttotokenlist, domssqlsqltexttotokenlist) which reads from lexer and populates sourcetokenlist.

      Example (Oracle): 

       protected void tokenizeVendorSql() {
     dooraclesqltexttotokenlist();
 }

      Example (MSSQL): 

       protected void tokenizeVendorSql() {
     domssqlsqltexttotokenlist();
 }

      Example (PostgreSQL): 

       protected void tokenizeVendorSql() {
     dopostgresqltexttotokenlist();
 }
      Specified by:
      tokenizeVendorSql in class AbstractSqlParser

    • setupVendorParsersForExtraction

      protected void setupVendorParsersForExtraction()
      Description copied from class: AbstractSqlParser
      Setup vendor-specific parsers for raw statement extraction.

      Hook Method: Called by AbstractSqlParser.extractRawStatements(gudusoft.gsqlparser.parser.ParserContext, gudusoft.gsqlparser.TSourceTokenList, gudusoft.gsqlparser.TCustomLexer, long) after initializing sqlcmds but before calling the vendor-specific extraction logic.

      Subclass Responsibility: Inject sqlcmds into vendor parser(s) and update their token lists. Examples:

      • Single parser (MSSQL): Inject into fparser only
      • Dual parsers (Oracle): Inject into both fparser and fplsqlparser

      Example (MSSQL): 

       protected void setupVendorParsersForExtraction() {
     this.fparser.sqlcmds = this.sqlcmds;
     this.fparser.sourcetokenlist = this.sourcetokenlist;
 }

      Example (Oracle with dual parsers): 

       protected void setupVendorParsersForExtraction() {
     this.fparser.sqlcmds = this.sqlcmds;
     this.fplsqlparser.sqlcmds = this.sqlcmds;
     this.fparser.sourcetokenlist = this.sourcetokenlist;
     this.fplsqlparser.sourcetokenlist = this.sourcetokenlist;
 }
      Specified by:
      setupVendorParsersForExtraction in class AbstractSqlParser

    • extractVendorRawStatements

      protected void extractVendorRawStatements(SqlParseResult.Builder builder)
      Description copied from class: AbstractSqlParser
      Call vendor-specific raw statement extraction logic.

      Hook Method: Called by AbstractSqlParser.extractRawStatements(gudusoft.gsqlparser.parser.ParserContext, gudusoft.gsqlparser.TSourceTokenList, gudusoft.gsqlparser.TCustomLexer, long) to execute the vendor-specific logic for identifying statement boundaries.

      Subclass Responsibility: Call the vendor-specific extraction method (e.g., dooraclegetrawsqlstatements, domssqlgetrawsqlstatements) passing the builder. The extraction method will populate the builder with raw statements.

      Example (Oracle): 

       protected void extractVendorRawStatements(SqlParseResult.Builder builder) {
     dooraclegetrawsqlstatements(builder);
 }

      Example (MSSQL): 

       protected void extractVendorRawStatements(SqlParseResult.Builder builder) {
     domssqlgetrawsqlstatements(builder);
 }
      Specified by:
      extractVendorRawStatements in class AbstractSqlParser
      Parameters:
      builder - the result builder to populate with raw statements

    • performParsing

      protected TStatementList performParsing(ParserContext context, TCustomParser parser, TCustomParser secondaryParser, TSourceTokenList tokens, TStatementList rawStatements)
      Description copied from class: AbstractSqlParser
      Perform actual parsing with syntax checking.

      Subclass Responsibility: Parse SQL using vendor-specific parser and optional secondary parser (e.g., PL/SQL for Oracle).

      Important: This method receives raw statements that have already been extracted by AbstractSqlParser.getrawsqlstatements(ParserContext). Subclasses should NOT re-extract statements - just parse each statement to build the AST.

      Example: 

       protected TStatementList performParsing(ParserContext context,
                                         TCustomParser parser,
                                         TCustomParser secondaryParser,
                                         TSourceTokenList tokens,
                                         TStatementList rawStatements) {
     // Use the passed-in rawStatements (DO NOT re-extract!)
     for (int i = 0; i < rawStatements.size(); i++) {
         TCustomSqlStatement stmt = rawStatements.get(i);
         stmt.parsestatement(...);  // Build AST for each statement
     }
     return rawStatements;
 }
      Specified by:
      performParsing in class AbstractSqlParser
      Parameters:
      context - the parser context
      parser - the main parser instance
      secondaryParser - secondary parser (may be null)
      tokens - the source token list
      rawStatements - raw statements already extracted (never null)
      Returns:
      statement list with parsed AST (never null)

    • performSemanticAnalysis

      protected void performSemanticAnalysis(ParserContext context, TStatementList statements)
      Description copied from class: AbstractSqlParser
      Perform semantic analysis on parsed statements.

      Hook Method: Default implementation does nothing. Override to provide vendor-specific semantic analysis.

      Typical Implementation:

      • Column-to-table resolution (TSQLResolver)
      • Dataflow analysis
      • Reference resolution
      • Scope resolution
      Overrides:
      performSemanticAnalysis in class AbstractSqlParser
      Parameters:
      context - the parser context
      statements - the parsed statements (mutable)

    • performInterpreter

      protected void performInterpreter(ParserContext context, TStatementList statements)
      Description copied from class: AbstractSqlParser
      Perform interpretation/evaluation on parsed statements.

      Hook Method: Default implementation does nothing. Override to provide AST interpretation/evaluation.

      Typical Implementation:

      • Execute simple SQL statements
      • Evaluate expressions
      • Constant folding
      • Static analysis
      Overrides:
      performInterpreter in class AbstractSqlParser
      Parameters:
      context - the parser context
      statements - the parsed statements (mutable)

    • onRawStatementCompleteVendorSpecific

      protected void onRawStatementCompleteVendorSpecific(TCustomSqlStatement statement)
      GaussDB-specific statement completion logic.

      Migrated from TGSqlParser.doongetrawsqlstatementevent() (lines 5129-5141).

      For CREATE PROCEDURE/FUNCTION statements, marks Oracle-style routines by setting special token codes to distinguish them from PostgreSQL-style routines.

      Overrides:
      onRawStatementCompleteVendorSpecific in class AbstractSqlParser
      Parameters:
      statement - the completed statement

    • getVendor

      public EDbVendor getVendor()
      Description copied from interface: SqlParser
      Get the database vendor this parser handles.
      Specified by:
      getVendor in interface SqlParser
      Overrides:
      getVendor in class AbstractSqlParser
      Returns:
      the database vendor (e.g., dbvoracle, dbvmysql)

    • toString

      public String toString()
      Overrides:
      toString in class AbstractSqlParser