Commit 78df234b authored by terrymanu's avatar terrymanu
Browse files

refactor: DerivedUtils = DerivedColumnUtils

parent 750cbf19

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/rewrite/DerivedUtils.java→sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/rewrite/DerivedColumnUtils.java

+10 −10
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ import com.google.common.base.Optional; 
 *

 * @author zhangliang

 */

public final class DerivedUtils {

public final class DerivedColumnUtils {

    

    private static final String DERIVED_COUNT_ALIAS = "AVG_DERIVED_COUNT_%s";
@@ -62,16 +62,16 @@ public final class DerivedUtils { 
            if (!(each instanceof AggregationSelectItemContext) || AggregationType.AVG != ((AggregationSelectItemContext) each).getAggregationType()) {

                continue;

            }

            AggregationSelectItemContext aggregationSelectItemContext = (AggregationSelectItemContext) each;

            AggregationSelectItemContext countSelectItemContext = new AggregationSelectItemContext(

                    aggregationSelectItemContext.getInnerExpression(), Optional.of(String.format(DERIVED_COUNT_ALIAS, derivedColumnOffset)), -1, AggregationType.COUNT);

            AggregationSelectItemContext sumSelectItemContext = new AggregationSelectItemContext(

                    aggregationSelectItemContext.getInnerExpression(), Optional.of(String.format(DERIVED_SUM_ALIAS, derivedColumnOffset)), -1, AggregationType.SUM);

            aggregationSelectItemContext.getDerivedAggregationSelectItemContexts().add(countSelectItemContext);

            aggregationSelectItemContext.getDerivedAggregationSelectItemContexts().add(sumSelectItemContext);

            AggregationSelectItemContext avgContext = (AggregationSelectItemContext) each;

            String countAlias = String.format(DERIVED_COUNT_ALIAS, derivedColumnOffset);

            AggregationSelectItemContext countContext = new AggregationSelectItemContext(avgContext.getInnerExpression(), Optional.of(countAlias), -1, AggregationType.COUNT);

            String sumAlias = String.format(DERIVED_SUM_ALIAS, derivedColumnOffset);

            AggregationSelectItemContext sumContext = new AggregationSelectItemContext(avgContext.getInnerExpression(), Optional.of(sumAlias), -1, AggregationType.SUM);

            avgContext.getDerivedAggregationSelectItemContexts().add(countContext);

            avgContext.getDerivedAggregationSelectItemContexts().add(sumContext);

            // TODO 将AVG列替换成常数，避免数据库再计算无用的AVG函数

            itemsToken.getItems().add(countSelectItemContext.getExpression() + " AS " + countSelectItemContext.getAlias().get() + " ");

            itemsToken.getItems().add(sumSelectItemContext.getExpression() + " AS " + sumSelectItemContext.getAlias().get() + " ");

            itemsToken.getItems().add(countContext.getExpression() + " AS " + countAlias + " ");

            itemsToken.getItems().add(sumContext.getExpression() + " AS " + sumAlias + " ");

            derivedColumnOffset++;

        }

    }

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/router/SQLRouteEngine.java

+2 −2
Original line number Diff line number Diff line
@@ -34,7 +34,7 @@ import com.dangdang.ddframe.rdb.sharding.parsing.parser.context.UpdateSQLContext 
import com.dangdang.ddframe.rdb.sharding.parsing.parser.exception.SQLParsingException;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountLimitToken;

import com.dangdang.ddframe.rdb.sharding.rewrite.DerivedUtils;

import com.dangdang.ddframe.rdb.sharding.rewrite.DerivedColumnUtils;

import com.dangdang.ddframe.rdb.sharding.rewrite.GenerateKeysUtils;

import com.dangdang.ddframe.rdb.sharding.rewrite.SQLBuilder;

import com.dangdang.ddframe.rdb.sharding.rewrite.SQLRewriteEngine;
@@ -100,7 +100,7 @@ public final class SQLRouteEngine { 
            GenerateKeysUtils.appendGenerateKeys(shardingRule, parameters, (InsertSQLContext) result);

        }

        if (result instanceof SelectSQLContext) {

            DerivedUtils.appendDerivedColumns((SelectSQLContext) result);

            DerivedColumnUtils.appendDerivedColumns((SelectSQLContext) result);

        }

        return result;

    }