[Enhancement] (nereids)implement showColumnsCommand in nereids

fe/fe-core/src/main/antlr4/org/apache/doris/nereids/DorisParser.g4

@@ -294,6 +294,8 @@ supportedShowStatement
     | SHOW TABLET DIAGNOSIS tabletId=INTEGER_VALUE                                  #showDiagnoseTablet
     | SHOW FRONTENDS name=identifier?                                               #showFrontends
     | SHOW DATABASE databaseId=INTEGER_VALUE                                        #showDatabaseId
+    | SHOW FULL? (COLUMNS | FIELDS) (FROM | IN) tableName=multipartIdentifier
+        ((FROM | IN) database=multipartIdentifier)? (LIKE STRING_LITERAL)?          #showColumns    
     | SHOW TABLE tableId=INTEGER_VALUE                                              #showTableId
     | SHOW TRASH (ON backend=STRING_LITERAL)?                                       #showTrash
     | SHOW (GLOBAL | SESSION | LOCAL)? STATUS                                       #showStatus

fe/fe-core/src/main/java/org/apache/doris/nereids/parser/LogicalPlanBuilder.java

@@ -277,6 +277,7 @@
 import org.apache.doris.nereids.DorisParser.ShowBrokerContext;
 import org.apache.doris.nereids.DorisParser.ShowCharsetContext;
 import org.apache.doris.nereids.DorisParser.ShowCollationContext;
+import org.apache.doris.nereids.DorisParser.ShowColumnsContext;
 import org.apache.doris.nereids.DorisParser.ShowConfigContext;
 import org.apache.doris.nereids.DorisParser.ShowConstraintContext;
 import org.apache.doris.nereids.DorisParser.ShowConvertLscContext;
@@ -567,6 +568,7 @@
 import org.apache.doris.nereids.trees.plans.commands.ShowCatalogCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowCharsetCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowCollationCommand;
+import org.apache.doris.nereids.trees.plans.commands.ShowColumnsCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowConfigCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowConstraintsCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowConvertLSCCommand;
@@ -5252,6 +5254,19 @@ public LogicalPlan visitShowSyncJob(ShowSyncJobContext ctx) {
         return new ShowSyncJobCommand(databaseName);
     }
 
+    @Override
+    public LogicalPlan visitShowColumns(ShowColumnsContext ctx) {
+        boolean isFull = ctx.FULL() != null;
+        List<String> nameParts = visitMultipartIdentifier(ctx.tableName);
+        String databaseName = ctx.database != null ? ctx.database.getText() : null;
+        String pattern = null;
+        if (ctx.LIKE() != null) {
+            pattern = stripQuotes(ctx.STRING_LITERAL().getText());
+        }
+
+        return new ShowColumnsCommand(isFull, new TableNameInfo(nameParts), databaseName, pattern);
+    }
+
     @Override
     public LogicalPlan visitDropFile(DropFileContext ctx) {
         String dbName = null;

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/PlanType.java

@@ -218,6 +218,7 @@ public enum PlanType {
     SHOW_CATALOG_COMMAND,
     SHOW_CHARSET_COMMAND,
     SHOW_COLLATION_COMMAND,
+    SHOW_COLUMNS_COMMAND,
     SHOW_CONFIG_COMMAND,
     SHOW_CREATE_CATALOG_COMMAND,
     SHOW_CREATE_DATABASE_COMMAND,

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/commands/ShowColumnsCommand.java

@@ -0,0 +1,161 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package org.apache.doris.nereids.trees.plans.commands;
+
+import org.apache.doris.catalog.Column;
+import org.apache.doris.catalog.DatabaseIf;
+import org.apache.doris.catalog.Env;
+import org.apache.doris.catalog.ScalarType;
+import org.apache.doris.catalog.TableIf;
+import org.apache.doris.common.AnalysisException;
+import org.apache.doris.common.CaseSensibility;
+import org.apache.doris.common.ErrorCode;
+import org.apache.doris.common.ErrorReport;
+import org.apache.doris.common.PatternMatcher;
+import org.apache.doris.common.PatternMatcherWrapper;
+import org.apache.doris.mysql.privilege.PrivPredicate;
+import org.apache.doris.nereids.trees.plans.PlanType;
+import org.apache.doris.nereids.trees.plans.commands.info.TableNameInfo;
+import org.apache.doris.nereids.trees.plans.visitor.PlanVisitor;
+import org.apache.doris.qe.ConnectContext;
+import org.apache.doris.qe.ShowResultSet;
+import org.apache.doris.qe.ShowResultSetMetaData;
+import org.apache.doris.qe.StmtExecutor;
+
+import com.google.common.base.Strings;
+import com.google.common.collect.Lists;
+
+import java.util.List;
+import java.util.Locale;
+
+/**
+ * Represents the SHOW COLUMNS command.
+ */
+public class ShowColumnsCommand extends ShowCommand {
+    private static final ShowResultSetMetaData META_DATA = ShowResultSetMetaData.builder()
+            .addColumn(new Column("Field", ScalarType.createVarchar(20)))
+            .addColumn(new Column("Type", ScalarType.createVarchar(20)))
+            .addColumn(new Column("Null", ScalarType.createVarchar(20)))
+            .addColumn(new Column("Key", ScalarType.createVarchar(20)))
+            .addColumn(new Column("Default", ScalarType.createVarchar(20)))
+            .addColumn(new Column("Extra", ScalarType.createVarchar(20))).build();
+
+    private static final ShowResultSetMetaData META_DATA_VERBOSE =
+            ShowResultSetMetaData.builder()
+                    .addColumn(new Column("Field", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Type", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Collation", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Null", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Key", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Default", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Extra", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Privileges", ScalarType.createVarchar(20)))
+                    .addColumn(new Column("Comment", ScalarType.createVarchar(20)))
+                    .build();
+
+    private ShowResultSetMetaData metaData;
+    private final boolean isFull;
+    private TableNameInfo tableNameInfo;
+    private final String databaseName;
+    private final String likePattern;
+
+    public ShowColumnsCommand(boolean isFull, TableNameInfo tableNameInfo, String databaseName, String likePattern) {
+        super(PlanType.SHOW_COLUMNS_COMMAND);
+        this.isFull = isFull;
+        this.tableNameInfo = tableNameInfo;
+        this.databaseName = databaseName;
+        this.likePattern = likePattern;
+    }
+
+    private void validate(ConnectContext ctx) throws AnalysisException {
+        if (!Strings.isNullOrEmpty(databaseName)) {
+            tableNameInfo.setDb(databaseName);
+        }
+        tableNameInfo.analyze(ctx);
+        if (isFull) {
+            metaData = META_DATA_VERBOSE;
+        } else {
+            metaData = META_DATA;
+        }
+        if (!Env.getCurrentEnv().getAccessManager()
+                .checkTblPriv(ConnectContext.get(), tableNameInfo.getCtl(), tableNameInfo.getDb(),
+                        tableNameInfo.getTbl(), PrivPredicate.SHOW)) {
+            ErrorReport.reportAnalysisException(ErrorCode.ERR_TABLE_ACCESS_DENIED_ERROR,
+                    PrivPredicate.SHOW.getPrivs().toString(), tableNameInfo);
+        }
+    }
+
+    @Override
+    public ShowResultSet doRun(ConnectContext ctx, StmtExecutor executor) throws Exception {
+        validate(ctx);
+        List<List<String>> rows = Lists.newArrayList();
+        String ctl = tableNameInfo.getCtl();
+        DatabaseIf db = Env.getCurrentEnv().getCatalogMgr().getCatalogOrAnalysisException(ctl)
+                .getDbOrAnalysisException(tableNameInfo.getDb());
+        TableIf table = db.getTableOrAnalysisException(tableNameInfo.getTbl());
+        PatternMatcher matcher = null;
+        if (likePattern != null) {
+            matcher = PatternMatcherWrapper.createMysqlPattern(likePattern,
+                    CaseSensibility.COLUMN.getCaseSensibility());
+        }
+        table.readLock();
+        try {
+            List<Column> columns = table.getBaseSchema();
+            for (Column col : columns) {
+                if (matcher != null && !matcher.match(col.getName())) {
+                    continue;
+                }
+                final String columnName = col.getName();
+                final String columnType = col.getOriginType().toString().toLowerCase(Locale.ROOT);
+                final String isAllowNull = col.isAllowNull() ? "YES" : "NO";
+                final String isKey = col.isKey() ? "YES" : "NO";
+                final String defaultValue = col.getDefaultValue();
+                final String aggType = col.getAggregationType() == null ? "" : col.getAggregationType().toSql();
+                if (isFull) {
+                    // Field Type Collation Null Key Default Extra
+                    // Privileges Comment
+                    rows.add(Lists.newArrayList(columnName,
+                            columnType,
+                            "",
+                            isAllowNull,
+                            isKey,
+                            defaultValue,
+                            aggType,
+                            "",
+                            col.getComment()));
+                } else {
+                    // Field Type Null Key Default Extra
+                    rows.add(Lists.newArrayList(columnName,
+                            columnType,
+                            isAllowNull,
+                            isKey,
+                            defaultValue,
+                            aggType));
+                }
+            }
+        } finally {
+            table.readUnlock();
+        }
+        return new ShowResultSet(metaData, rows);
+    }
+
+    @Override
+    public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
+        return visitor.visitShowColumnsCommand(this, context);
+    }
+}

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/visitor/CommandVisitor.java

@@ -97,6 +97,7 @@
 import org.apache.doris.nereids.trees.plans.commands.ShowCatalogCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowCharsetCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowCollationCommand;
+import org.apache.doris.nereids.trees.plans.commands.ShowColumnsCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowConfigCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowConstraintsCommand;
 import org.apache.doris.nereids.trees.plans.commands.ShowConvertLSCCommand;
@@ -369,6 +370,10 @@ default R visitAlterViewCommand(AlterViewCommand alterViewCommand, C context) {
         return visitCommand(alterViewCommand, context);
     }
 
+    default R visitShowColumnsCommand(ShowColumnsCommand showColumnsCommand, C context) {
+        return visitCommand(showColumnsCommand, context);
+    }
+
     default R visitDropCatalogCommand(DropCatalogCommand dropCatalogCommand, C context) {
         return visitCommand(dropCatalogCommand, context);
     }

regression-test/data/nereids_p0/show/test_show_columns_command.out

@@ -0,0 +1,14 @@
+-- This file is automatically generated. You should know what you did if you want to edit this
+-- !cmd --
+id	int	YES	YES	\N	
+name	text	YES	NO	\N	NONE
+score	float	YES	NO	\N	NONE
+
+-- !cmd --
+id	int		YES	YES	\N			
+name	text		YES	NO	\N	NONE		
+score	float		YES	NO	\N	NONE		
+
+-- !cmd --
+score	float	YES	NO	\N	NONE
+

regression-test/suites/nereids_p0/show/test_show_columns_command.groovy

@@ -0,0 +1,50 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+suite("test_show_columns_command", "nereids_p0") {
+    def dbName = "test_show_columns_db"
+    def tableName = "test_show_columns_table"
+
+    try {
+        sql """CREATE DATABASE IF NOT EXISTS ${dbName}"""
+        sql """
+            CREATE TABLE IF NOT EXISTS ${dbName}.${tableName} (
+                id INT,
+                name STRING,
+                score FLOAT
+            )
+            DISTRIBUTED BY HASH(id) BUCKETS 3
+            PROPERTIES ("replication_num" = "1");
+        """
+
+        // Test SHOW COLUMNS
+        checkNereidsExecute("""SHOW COLUMNS FROM ${dbName}.${tableName}""")
+        qt_cmd("""SHOW COLUMNS FROM ${dbName}.${tableName}""")
+
+        // Test SHOW FULL COLUMNS
+        checkNereidsExecute("""SHOW FULL COLUMNS FROM ${dbName}.${tableName}""")
+        qt_cmd("""SHOW FULL COLUMNS FROM ${dbName}.${tableName}""")
+
+        // Test SHOW COLUMNS with LIKE
+        checkNereidsExecute("""SHOW COLUMNS FROM ${dbName}.${tableName} LIKE 's%'""")
+        qt_cmd("""SHOW COLUMNS FROM ${dbName}.${tableName} LIKE 's%'""")
+
+    } finally {
+        sql """DROP TABLE IF EXISTS ${dbName}.${tableName}"""
+        sql """DROP DATABASE IF EXISTS ${dbName}"""
+    }
+}