Alawn/Druid
1
0
Fork 0
mirror of https://github.com/alibaba/druid.git synced 2023-03-04 19:17:16 +00:00
Code Issues Releases Wiki Activity

improve sql parser perforamnce

Browse Source
This commit is contained in:
wenshao
2013-01-14 03:26:26 +08:00
parent 368a3b3239
commit cb45e49a0c
5 changed files with 237 additions and 49 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/main/java/com/alibaba/druid/sql/parser/SQLSelectParser.java
+25 -5
View File
@@ -15,6 +15,8 @@
*/
package com.alibaba.druid.sql.parser;
import java.util.List;
import com.alibaba.druid.sql.ast.SQLExpr;
import com.alibaba.druid.sql.ast.SQLOrderBy;
import com.alibaba.druid.sql.ast.SQLSetQuantifier;
@@ -243,12 +245,30 @@ public class SQLSelectParser extends SQLParser {
}
}
protected void parseSelectList(SQLSelectQueryBlock queryBlock) {
queryBlock.getSelectList().add(new SQLSelectItem(expr(), as()));
while (lexer.token() == Token.COMMA) {
protected final void parseSelectList(SQLSelectQueryBlock queryBlock) {
final List<SQLSelectItem> selectList = queryBlock.getSelectList();
for (;;) {
SQLExpr expr;
if (lexer.token() == Token.IDENTIFIER) {
expr = new SQLIdentifierExpr(lexer.stringVal());
lexer.nextTokenComma();
if (lexer.token() != Token.COMMA) {
expr = this.exprParser.primaryRest(expr);
expr = this.exprParser.exprRest(expr);
}
} else {
expr = expr();
}
final String alias = as();
final SQLSelectItem selectItem = new SQLSelectItem(expr, alias);
selectList.add(selectItem);
if (lexer.token() != Token.COMMA) {
break;
}
lexer.nextToken();
queryBlock.getSelectList().add(new SQLSelectItem(expr(), as()));
}
}