Reduce use of LOB columns (#5799)

* Reducer LOB usage in Batch2 and Search (#5748) * Reducer LOB usage in Batch2 and Search * Add changelog * Rework a number of LOB columns * Test fix * Test fix * Column fixes * Test fix * Formatting * Fixes * patching bad oracle test * Apply spotless --------- Co-authored-by: Tadgh <garygrantgraham@gmail.com> * Clean up * Revert change * One more revert * Resolve compile issue --------- Co-authored-by: Tadgh <garygrantgraham@gmail.com>
2024-03-27 14:19:07 -04:00 · 2024-03-27 14:19:07 -04:00 · 6175807f58
parent 2f9693a1e4
commit 6175807f58
12 changed files with 133 additions and 42 deletions
--- a/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_2_0/5748-avoid-lob-usage-in-batch2-and-search.yaml
+++ b/hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_2_0/5748-avoid-lob-usage-in-batch2-and-search.yaml
@ -0,0 +1,8 @@
+---
+type: perf
+issue: 5748
+title: "In the JPA server, several database columns related to Batch2 jobs and searching
+   have been reworked so that they no will longer use LOB datatypes going forward. This
+   is a significant advantage on Postgresql databases as it removes a significant use
+   of the inefficient `pg_largeobject` table, and should yield performance boosts for
+   MSSQL as well."
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/data/IBatch2JobInstanceRepository.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/data/IBatch2JobInstanceRepository.java
@ -55,14 +55,15 @@ public interface IBatch2JobInstanceRepository
 	int updateWorkChunksPurgedTrue(@Param("id") String theInstanceId);

 	@Query(
-			"SELECT b from Batch2JobInstanceEntity b WHERE b.myDefinitionId = :defId AND b.myParamsJson = :params AND b.myStatus IN( :stats )")
+			"SELECT b from Batch2JobInstanceEntity b WHERE b.myDefinitionId = :defId AND (b.myParamsJson = :params OR b.myParamsJsonVc = :params) AND b.myStatus IN( :stats )")
 	List<Batch2JobInstanceEntity> findInstancesByJobIdParamsAndStatus(
 			@Param("defId") String theDefinitionId,
 			@Param("params") String theParams,
 			@Param("stats") Set<StatusEnum> theStatus,
 			Pageable thePageable);

-	@Query("SELECT b from Batch2JobInstanceEntity b WHERE b.myDefinitionId = :defId AND b.myParamsJson = :params")
+	@Query(
+			"SELECT b from Batch2JobInstanceEntity b WHERE b.myDefinitionId = :defId AND (b.myParamsJson = :params OR b.myParamsJsonVc = :params)")
 	List<Batch2JobInstanceEntity> findInstancesByJobIdAndParams(
 			@Param("defId") String theDefinitionId, @Param("params") String theParams, Pageable thePageable);

--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/data/IBatch2WorkChunkRepository.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/data/IBatch2WorkChunkRepository.java
@ -65,7 +65,7 @@ public interface IBatch2WorkChunkRepository

 	@Modifying
 	@Query("UPDATE Batch2WorkChunkEntity e SET e.myStatus = :status, e.myEndTime = :et, "
-			+ "e.myRecordsProcessed = :rp, e.myErrorCount = e.myErrorCount + :errorRetries, e.mySerializedData = null, "
+			+ "e.myRecordsProcessed = :rp, e.myErrorCount = e.myErrorCount + :errorRetries, e.mySerializedData = null, e.mySerializedDataVc = null, "
 			+ "e.myWarningMessage = :warningMessage WHERE e.myId = :id")
 	void updateChunkStatusAndClearDataForEndSuccess(
 			@Param("id") String theChunkId,
@ -77,7 +77,7 @@ public interface IBatch2WorkChunkRepository

 	@Modifying
 	@Query(
-			"UPDATE Batch2WorkChunkEntity e SET e.myStatus = :status, e.myEndTime = :et, e.mySerializedData = null, e.myErrorMessage = :em WHERE e.myId IN(:ids)")
+			"UPDATE Batch2WorkChunkEntity e SET e.myStatus = :status, e.myEndTime = :et, e.mySerializedData = null, e.mySerializedDataVc = null, e.myErrorMessage = :em WHERE e.myId IN(:ids)")
 	void updateAllChunksForInstanceStatusClearDataAndSetError(
 			@Param("ids") List<String> theChunkIds,
 			@Param("et") Date theEndTime,
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/Batch2JobInstanceEntity.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/Batch2JobInstanceEntity.java
@ -36,6 +36,7 @@ import jakarta.persistence.TemporalType;
 import jakarta.persistence.Version;
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.apache.commons.lang3.builder.ToStringStyle;
+import org.hibernate.Length;

 import java.io.Serializable;
 import java.util.Date;
@ -95,13 +96,17 @@ public class Batch2JobInstanceEntity implements Serializable {
 	@Column(name = "FAST_TRACKING", nullable = true)
 	private Boolean myFastTracking;

+	// TODO: VC column added in 7.2.0 - Remove non-VC column later
 	@Column(name = "PARAMS_JSON", length = PARAMS_JSON_MAX_LENGTH, nullable = true)
 	private String myParamsJson;

-	@Lob
+	@Lob // TODO: VC column added in 7.2.0 - Remove non-VC column later
 	@Column(name = "PARAMS_JSON_LOB", nullable = true)
 	private String myParamsJsonLob;

+	@Column(name = "PARAMS_JSON_VC", nullable = true, length = Length.LONG32)
+	private String myParamsJsonVc;
+
 	@Column(name = "CMB_RECS_PROCESSED", nullable = true)
 	private Integer myCombinedRecordsProcessed;

@ -142,11 +147,14 @@ public class Batch2JobInstanceEntity implements Serializable {
 	 * Any output from the job can be held in this column
 	 * Even serialized json
 	 */
-	@Lob
+	@Lob // TODO: VC column added in 7.2.0 - Remove non-VC column later
 	@Basic(fetch = FetchType.LAZY)
 	@Column(name = "REPORT", nullable = true, length = Integer.MAX_VALUE - 1)
 	private String myReport;

+	@Column(name = "REPORT_VC", nullable = true, length = Length.LONG32)
+	private String myReportVc;
+
 	public String getCurrentGatedStepId() {
 		return myCurrentGatedStepId;
 	}
@ -260,6 +268,9 @@ public class Batch2JobInstanceEntity implements Serializable {
 	}

 	public String getParams() {
+		if (myParamsJsonVc != null) {
+			return myParamsJsonVc;
+		}
 		if (myParamsJsonLob != null) {
 			return myParamsJsonLob;
 		}
@ -267,13 +278,9 @@ public class Batch2JobInstanceEntity implements Serializable {
 	}

 	public void setParams(String theParams) {
+		myParamsJsonVc = theParams;
 		myParamsJsonLob = null;
 		myParamsJson = null;
-		if (theParams != null && theParams.length() > PARAMS_JSON_MAX_LENGTH) {
-			myParamsJsonLob = theParams;
-		} else {
-			myParamsJson = theParams;
-		}
 	}

 	public boolean getWorkChunksPurged() {
@ -309,11 +316,12 @@ public class Batch2JobInstanceEntity implements Serializable {
 	}

 	public String getReport() {
-		return myReport;
+		return myReportVc != null ? myReportVc : myReport;
 	}

 	public void setReport(String theReport) {
-		myReport = theReport;
+		myReportVc = theReport;
+		myReport = null;
 	}

 	public String getWarningMessages() {
@ -362,7 +370,7 @@ public class Batch2JobInstanceEntity implements Serializable {
 				.append("progress", myProgress)
 				.append("errorMessage", myErrorMessage)
 				.append("estimatedTimeRemaining", myEstimatedTimeRemaining)
-				.append("report", myReport)
+				.append("report", getReport())
 				.append("warningMessages", myWarningMessages)
 				.append("initiatingUsername", myTriggeringUsername)
 				.append("initiatingclientId", myTriggeringClientId)
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/Batch2WorkChunkEntity.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/Batch2WorkChunkEntity.java
@ -38,6 +38,7 @@ import jakarta.persistence.TemporalType;
 import jakarta.persistence.Version;
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.apache.commons.lang3.builder.ToStringStyle;
+import org.hibernate.Length;

 import java.io.Serializable;
 import java.util.Date;
@ -92,11 +93,14 @@ public class Batch2WorkChunkEntity implements Serializable {
 	@Column(name = "TGT_STEP_ID", length = ID_MAX_LENGTH, nullable = false)
 	private String myTargetStepId;

-	@Lob
+	@Lob // TODO: VC column added in 7.2.0 - Remove non-VC column later
 	@Basic(fetch = FetchType.LAZY)
 	@Column(name = "CHUNK_DATA", nullable = true, length = Integer.MAX_VALUE - 1)
 	private String mySerializedData;

+	@Column(name = "CHUNK_DATA_VC", nullable = true, length = Length.LONG32)
+	private String mySerializedDataVc;
+
 	@Column(name = "STAT", length = STATUS_MAX_LENGTH, nullable = false)
 	@Enumerated(EnumType.STRING)
 	private WorkChunkStatusEnum myStatus;
@ -263,11 +267,12 @@ public class Batch2WorkChunkEntity implements Serializable {
 	}

 	public String getSerializedData() {
-		return mySerializedData;
+		return mySerializedDataVc != null ? mySerializedDataVc : mySerializedData;
 	}

 	public void setSerializedData(String theSerializedData) {
-		mySerializedData = theSerializedData;
+		mySerializedData = null;
+		mySerializedDataVc = theSerializedData;
 	}

 	public WorkChunkStatusEnum getStatus() {
@ -309,7 +314,7 @@ public class Batch2WorkChunkEntity implements Serializable {
 				.append("updateTime", myUpdateTime)
 				.append("recordsProcessed", myRecordsProcessed)
 				.append("targetStepId", myTargetStepId)
-				.append("serializedData", mySerializedData)
+				.append("serializedData", getSerializedData())
 				.append("status", myStatus)
 				.append("errorMessage", myErrorMessage)
 				.append("warningMessage", myWarningMessage)
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/BulkImportJobFileEntity.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/BulkImportJobFileEntity.java
@ -32,6 +32,7 @@ import jakarta.persistence.Lob;
 import jakarta.persistence.ManyToOne;
 import jakarta.persistence.SequenceGenerator;
 import jakarta.persistence.Table;
+import org.hibernate.Length;

 import java.io.Serializable;
 import java.nio.charset.StandardCharsets;
@ -66,10 +67,13 @@ public class BulkImportJobFileEntity implements Serializable {
 	@Column(name = "FILE_DESCRIPTION", nullable = true, length = MAX_DESCRIPTION_LENGTH)
 	private String myFileDescription;

-	@Lob
-	@Column(name = "JOB_CONTENTS", nullable = false)
+	@Lob // TODO: VC column added in 7.2.0 - Remove non-VC column later
+	@Column(name = "JOB_CONTENTS", nullable = true)
 	private byte[] myContents;

+	@Column(name = "JOB_CONTENTS_VC", nullable = true, length = Length.LONG32)
+	private String myContentsVc;
+
 	@Column(name = "TENANT_NAME", nullable = true, length = PartitionEntity.MAX_NAME_LENGTH)
 	private String myTenantName;

@ -98,11 +102,16 @@ public class BulkImportJobFileEntity implements Serializable {
 	}

 	public String getContents() {
-		return new String(myContents, StandardCharsets.UTF_8);
+		if (myContentsVc != null) {
+			return myContentsVc;
+		} else {
+			return new String(myContents, StandardCharsets.UTF_8);
+		}
 	}

 	public void setContents(String theContents) {
-		myContents = theContents.getBytes(StandardCharsets.UTF_8);
+		myContentsVc = theContents;
+		myContents = null;
 	}

 	public BulkImportJobFileJson toJson() {
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/Search.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/entity/Search.java
@ -50,6 +50,7 @@ import jakarta.persistence.UniqueConstraint;
 import jakarta.persistence.Version;
 import org.apache.commons.lang3.SerializationUtils;
 import org.apache.commons.lang3.builder.ToStringBuilder;
+import org.hibernate.Length;
 import org.hibernate.annotations.JdbcTypeCode;
 import org.hibernate.annotations.OptimisticLock;
 import org.hibernate.type.SqlTypes;
@ -141,14 +142,21 @@ public class Search implements ICachedSearchDetails, Serializable {

 	@Column(name = "RESOURCE_TYPE", length = 200, nullable = true)
 	private String myResourceType;
+
 	/**
 	 * Note that this field may have the request partition IDs prepended to it
 	 */
-	@Lob()
+	@Lob // TODO: VC column added in 7.2.0 - Remove non-VC column later
 	@Basic(fetch = FetchType.LAZY)
 	@Column(name = "SEARCH_QUERY_STRING", nullable = true, updatable = false, length = MAX_SEARCH_QUERY_STRING)
 	private String mySearchQueryString;

+	/**
+	 * Note that this field may have the request partition IDs prepended to it
+	 */
+	@Column(name = "SEARCH_QUERY_STRING_VC", nullable = true, length = Length.LONG32)
+	private String mySearchQueryStringVc;
+
 	@Column(name = "SEARCH_QUERY_STRING_HASH", nullable = true, updatable = false)
 	private Integer mySearchQueryStringHash;

@ -172,10 +180,13 @@ public class Search implements ICachedSearchDetails, Serializable {
 	@Column(name = "OPTLOCK_VERSION", nullable = true)
 	private Integer myVersion;

-	@Lob
+	@Lob // TODO: VC column added in 7.2.0 - Remove non-VC column later
 	@Column(name = "SEARCH_PARAM_MAP", nullable = true)
 	private byte[] mySearchParameterMap;

+	@Column(name = "SEARCH_PARAM_MAP_BIN", nullable = true, length = Length.LONG32)
+	private byte[] mySearchParameterMapBin;
+
 	@Transient
 	private transient SearchParameterMap mySearchParameterMapTransient;

@ -350,7 +361,7 @@ public class Search implements ICachedSearchDetails, Serializable {
 	 * Note that this field may have the request partition IDs prepended to it
 	 */
 	public String getSearchQueryString() {
-		return mySearchQueryString;
+		return mySearchQueryStringVc != null ? mySearchQueryStringVc : mySearchQueryString;
 	}

 	public void setSearchQueryString(String theSearchQueryString, RequestPartitionId theRequestPartitionId) {
@ -362,12 +373,13 @@ public class Search implements ICachedSearchDetails, Serializable {
 			// We want this field to always have a wide distribution of values in order
 			// to avoid optimizers avoiding using it if it has lots of nulls, so in the
 			// case of null, just put a value that will never be hit
-			mySearchQueryString = UUID.randomUUID().toString();
+			mySearchQueryStringVc = UUID.randomUUID().toString();
 		} else {
-			mySearchQueryString = searchQueryString;
+			mySearchQueryStringVc = searchQueryString;
 		}

-		mySearchQueryStringHash = mySearchQueryString.hashCode();
+		mySearchQueryString = null;
+		mySearchQueryStringHash = mySearchQueryStringVc.hashCode();
 	}

 	public SearchTypeEnum getSearchType() {
@ -466,8 +478,12 @@ public class Search implements ICachedSearchDetails, Serializable {
 			return Optional.of(mySearchParameterMapTransient);
 		}
 		SearchParameterMap searchParameterMap = null;
-		if (mySearchParameterMap != null) {
-			searchParameterMap = SerializationUtils.deserialize(mySearchParameterMap);
+		byte[] searchParameterMapSerialized = mySearchParameterMapBin;
+		if (searchParameterMapSerialized == null) {
+			searchParameterMapSerialized = mySearchParameterMap;
+		}
+		if (searchParameterMapSerialized != null) {
+			searchParameterMap = SerializationUtils.deserialize(searchParameterMapSerialized);
 			mySearchParameterMapTransient = searchParameterMap;
 		}
 		return Optional.ofNullable(searchParameterMap);
@ -475,7 +491,8 @@ public class Search implements ICachedSearchDetails, Serializable {

 	public void setSearchParameterMap(SearchParameterMap theSearchParameterMap) {
 		mySearchParameterMapTransient = theSearchParameterMap;
-		mySearchParameterMap = SerializationUtils.serialize(theSearchParameterMap);
+		mySearchParameterMapBin = SerializationUtils.serialize(theSearchParameterMap);
+		mySearchParameterMap = null;
 	}

 	@Override
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/migrate/tasks/HapiFhirJpaMigrationTasks.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/migrate/tasks/HapiFhirJpaMigrationTasks.java
@ -117,6 +117,7 @@ public class HapiFhirJpaMigrationTasks extends BaseMigrationTasks<VersionEnum> {
 		init640_after_20230126();
 		init660();
 		init680();
+		init680_Part2();
 		init700();
 	}

@ -218,6 +219,44 @@ public class HapiFhirJpaMigrationTasks extends BaseMigrationTasks<VersionEnum> {
 		version.addTask(new ForceIdMigrationFixTask(version.getRelease(), "20231222.1"));
 	}

+	private void init680_Part2() {
+		Builder version = forVersion(VersionEnum.V6_8_0);
+
+		// Add additional LOB migration columns
+		version.onTable("BT2_JOB_INSTANCE")
+				.addColumn("20240227.1", "REPORT_VC")
+				.nullable()
+				.type(ColumnTypeEnum.TEXT);
+		version.onTable("BT2_JOB_INSTANCE")
+				.addColumn("20240227.2", "PARAMS_JSON_VC")
+				.nullable()
+				.type(ColumnTypeEnum.TEXT);
+
+		version.onTable("BT2_WORK_CHUNK")
+				.addColumn("20240227.3", "CHUNK_DATA_VC")
+				.nullable()
+				.type(ColumnTypeEnum.TEXT);
+
+		version.onTable("HFJ_SEARCH")
+				.addColumn("20240227.4", "SEARCH_QUERY_STRING_VC")
+				.nullable()
+				.type(ColumnTypeEnum.TEXT);
+		version.onTable("HFJ_SEARCH")
+				.addColumn("20240227.5", "SEARCH_PARAM_MAP_BIN")
+				.nullable()
+				.type(ColumnTypeEnum.BINARY);
+
+		version.onTable("HFJ_BLK_IMPORT_JOBFILE")
+				.addColumn("20240227.6", "JOB_CONTENTS_VC")
+				.nullable()
+				.type(ColumnTypeEnum.TEXT);
+
+		version.onTable("HFJ_BLK_IMPORT_JOBFILE")
+				.modifyColumn("20240227.7", "JOB_CONTENTS")
+				.nullable()
+				.withType(ColumnTypeEnum.BLOB);
+	}
+
 	protected void init680() {
 		Builder version = forVersion(VersionEnum.V6_8_0);
 		// HAPI-FHIR #4801 - Add New Index On HFJ_RESOURCE
--- a/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/JdbcUtils.java
+++ b/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/JdbcUtils.java
@ -207,14 +207,7 @@ public class JdbcUtils {
 							case Types.BLOB:
 								return new ColumnType(ColumnTypeEnum.BLOB, length);
 							case Types.LONGVARBINARY:
-								if (DriverTypeEnum.MYSQL_5_7.equals(theConnectionProperties.getDriverType())) {
-									// See git
-									return new ColumnType(ColumnTypeEnum.BLOB, length);
-								} else {
-									throw new IllegalArgumentException(
-											Msg.code(32) + "Don't know how to handle datatype " + dataType
-													+ " for column " + theColumnName + " on table " + theTableName);
-								}
+								return new ColumnType(ColumnTypeEnum.BINARY, length);
 							case Types.VARBINARY:
 								if (DriverTypeEnum.MSSQL_2012.equals(theConnectionProperties.getDriverType())) {
 									// MS SQLServer seems to be mapping BLOB to VARBINARY under the covers, so we need
--- a/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/taskdef/ColumnTypeEnum.java
+++ b/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/taskdef/ColumnTypeEnum.java
@ -37,5 +37,7 @@ public enum ColumnTypeEnum {
 	 * <code>@Column(length=Integer.MAX_VALUE)</code>
 	 */
 	TEXT,
+	/** Long inline binary */
+	BINARY,
 	BIG_DECIMAL;
 }
--- a/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/taskdef/ColumnTypeToDriverTypeToSqlType.java
+++ b/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/taskdef/ColumnTypeToDriverTypeToSqlType.java
@ -131,6 +131,14 @@ public final class ColumnTypeToDriverTypeToSqlType {
 		setColumnType(ColumnTypeEnum.TEXT, DriverTypeEnum.POSTGRES_9_4, "text");
 		setColumnType(ColumnTypeEnum.TEXT, DriverTypeEnum.MSSQL_2012, "varchar(MAX)");

+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.H2_EMBEDDED, "blob");
+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.DERBY_EMBEDDED, "blob");
+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.MARIADB_10_1, "longblob");
+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.MYSQL_5_7, "longblob");
+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.ORACLE_12C, "blob");
+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.POSTGRES_9_4, "bytea");
+		setColumnType(ColumnTypeEnum.BINARY, DriverTypeEnum.MSSQL_2012, "varbinary(MAX)");
+
 		setColumnType(ColumnTypeEnum.BIG_DECIMAL, DriverTypeEnum.H2_EMBEDDED, "numeric(38,2)");
 		setColumnType(ColumnTypeEnum.BIG_DECIMAL, DriverTypeEnum.DERBY_EMBEDDED, "decimal(31,2)");
 		setColumnType(ColumnTypeEnum.BIG_DECIMAL, DriverTypeEnum.MARIADB_10_1, "decimal(38,2)");
--- a/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/taskdef/ModifyColumnTask.java
+++ b/hapi-fhir-sql-migrate/src/main/java/ca/uhn/fhir/jpa/migrate/taskdef/ModifyColumnTask.java
@ -133,9 +133,10 @@ public class ModifyColumnTask extends BaseTableColumnTypeTask {
 				}
 				break;
 			case ORACLE_12C:
-				String oracleNullableStmt = !alreadyCorrectNullable ? notNull : "";
-				sql = "alter table " + getTableName() + " modify ( " + getColumnName() + " " + type + oracleNullableStmt
-						+ " )";
+				String oracleNullableStmt = alreadyCorrectNullable ? "" : notNull;
+				String oracleTypeStmt = alreadyOfCorrectType ? "" : type;
+				sql = "alter table " + getTableName() + " modify ( " + getColumnName() + " " + oracleTypeStmt + " "
+						+ oracleNullableStmt + " )";
 				break;
 			case MSSQL_2012:
 				sql = "alter table " + getTableName() + " alter column " + getColumnName() + " " + type + notNull;