gudusoft.gsqlparser.parser

Class SnowflakeSqlParser

Object

gudusoft.gsqlparser.parser.AbstractSqlParser

gudusoft.gsqlparser.parser.SnowflakeSqlParser

All Implemented Interfaces:

SqlParser

public class SnowflakeSqlParser
extends AbstractSqlParser

Snowflake database SQL parser implementation.

This parser handles Snowflake-specific SQL syntax including:

• Snowflake stored procedures (SQL and JavaScript)
• Snowflake-specific functions (FLATTEN, PIVOT, UNPIVOT, etc.)
• Snowflake tasks and streams
• Snowflake semi-structured data handling (VARIANT, ARRAY, OBJECT)
• Special token handling (AT, LEFT/RIGHT joins, DATE/TIME functions)
• Transaction control (BEGIN TRANSACTION, COMMIT, ROLLBACK)

Design Notes:

• Extends AbstractSqlParser using the template method pattern
• Uses TLexerSnowflake for tokenization
• Uses TParserSnowflake for parsing
• Delimiter character: ';' for SQL statements

Usage Example:

 // Get Snowflake parser from factory
 SqlParser parser = SqlParserFactory.get(EDbVendor.dbvsnowflake);

 // Build context
 ParserContext context = new ParserContext.Builder(EDbVendor.dbvsnowflake)
     .sqlText("SELECT * FROM customers WHERE region = 'US'")
     .build();

 // Parse
 SqlParseResult result = parser.parse(context);

 // Access statements
 TStatementList statements = result.getSqlStatements();
 

Since:

3.2.0.0

See Also:

SqlParser, AbstractSqlParser, TLexerSnowflake, TParserSnowflake

Nested Class Summary

Nested classes/interfaces inherited from class gudusoft.gsqlparser.parser.AbstractSqlParser

AbstractSqlParser.PreparedSqlReader

Field Summary

Fields

Modifier and Type	Field and Description
TLexerSnowflake	flexer The Snowflake lexer used for tokenization

Fields inherited from class gudusoft.gsqlparser.parser.AbstractSqlParser

defaultDelimiterStr, delimiterChar, frameStack, globalContext, globalFrame, lexer, parserContext, sourcetokenlist, sqlcmds, sqlEnv, sqlstatements, syntaxErrors, vendor

Constructor Summary

Constructors

Constructor and Description
SnowflakeSqlParser() Construct Snowflake SQL parser.

Method Summary

Modifier and Type	Method and Description
protected void	extractVendorRawStatements(SqlParseResult.Builder builder) Call Snowflake-specific raw statement extraction logic.
protected TCustomLexer	getLexer(ParserContext context) Return the Snowflake lexer instance.
protected TCustomParser	getParser(ParserContext context, TSourceTokenList tokens) Return the Snowflake SQL parser instance with updated token list.
protected TCustomParser	getSecondaryParser(ParserContext context, TSourceTokenList tokens) Snowflake does not use a secondary parser (unlike Oracle with PL/SQL).
protected void	performInterpreter(ParserContext context, TStatementList statements) Perform interpretation/evaluation on parsed statements.
protected TStatementList	performParsing(ParserContext context, TCustomParser parser, TCustomParser secondaryParser, TSourceTokenList tokens, TStatementList rawStatements) Perform full parsing of statements with syntax checking.
protected void	performSemanticAnalysis(ParserContext context, TStatementList statements) Perform Snowflake-specific semantic analysis using TSQLResolver.
protected void	setupVendorParsersForExtraction() Setup Snowflake parser for raw statement extraction.
protected void	tokenizeVendorSql() Call Snowflake-specific tokenization logic.
String	toString()

Methods inherited from class gudusoft.gsqlparser.parser.AbstractSqlParser

afterStatementParsed, attemptErrorRecovery, copyErrorsFromStatement, doAfterTokenize, doExtractRawStatements, extractRawStatements, getanewsourcetoken, getDefaultDelimiterStr, getDelimiterChar, getErrorCount, getrawsqlstatements, getSyntaxErrors, getVendor, handleStatementParsingException, initializeGlobalContext, isDollarFunctionDelimiter, onRawStatementComplete, onRawStatementCompleteVendorSpecific, parse, performTokenization, prepareSqlReader, processTokensBeforeParse, processTokensInTokenTable, setTokenHandle, tokenize, towinlinebreak

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

flexer

public TLexerSnowflake flexer

The Snowflake lexer used for tokenization

Constructor Detail

SnowflakeSqlParser

public SnowflakeSqlParser()

Construct Snowflake SQL parser.

Configures the parser for Snowflake database with default delimiter (;).

Following the original TGSqlParser pattern, the lexer and parser are created once in the constructor and reused for all parsing operations.

Method Detail

getLexer

protected TCustomLexer getLexer(ParserContext context)

Return the Snowflake lexer instance.

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)

Return the Snowflake SQL parser instance with updated token list.

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)

Snowflake does not use a secondary parser (unlike Oracle with PL/SQL).

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()

Call Snowflake-specific tokenization logic.

Delegates to dosnowflakesqltexttotokenlist which handles Snowflake's specific keyword recognition and token generation.

Specified by:

tokenizeVendorSql in class AbstractSqlParser

setupVendorParsersForExtraction

protected void setupVendorParsersForExtraction()

Setup Snowflake parser for raw statement extraction.

Snowflake uses a single parser, so we inject sqlcmds and update the token list for the main parser only.

Specified by:

setupVendorParsersForExtraction in class AbstractSqlParser

extractVendorRawStatements

protected void extractVendorRawStatements(SqlParseResult.Builder builder)

Call Snowflake-specific raw statement extraction logic.

Delegates to dosnowflakegetrawsqlstatements which handles Snowflake's statement delimiters and stored procedure boundaries.

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)

Perform full parsing of statements with syntax checking.

This method orchestrates the parsing of all statements.

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)

Perform Snowflake-specific semantic analysis using TSQLResolver.

Overrides:

performSemanticAnalysis in class AbstractSqlParser

Parameters:

context - the parser context

statements - the parsed statements (mutable)

performInterpreter

protected void performInterpreter(ParserContext context,
                                  TStatementList statements)

Perform interpretation/evaluation on parsed statements.

Overrides:

performInterpreter in class AbstractSqlParser

Parameters:

context - the parser context

statements - the parsed statements (mutable)

toString

public String toString()

Overrides:

toString in class AbstractSqlParser