Mode

java.lang.Object
- org.h2.engine.Mode

```
public class Mode
extends java.lang.Object
```
The compatibility modes. There is a fixed set of modes (for example PostgreSQL, MySQL). Each mode has different settings.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Mode.CharPadding` When CHAR values are right-padded with spaces.
`static class`	`Mode.ExpressionNames` Generation of column names for expressions.
`static class`	`Mode.ModeEnum`
`static class`	`Mode.ViewExpressionNames` Generation of column names for expressions to be used in a view.

Field Summary

Fields
Modifier and Type	Field and Description
`boolean`	`acceptsCommaAsJsonKeyValueSeparator` Accepts comma ',' as key/value separator in JSON_OBJECT and JSON_OBJECTAGG functions.
`boolean`	`aliasColumnName` When enabled, aliased columns (as in SELECT ID AS I FROM TEST) return the alias (I in this case) in ResultSetMetaData.getColumnName() and 'null' in getTableName().
`boolean`	`allNumericTypesHavePrecision` If `true` all numeric data types may have precision and 'UNSIGNED' clause.
`boolean`	`allowDB2TimestampFormat` Whether DB2 TIMESTAMP formats are allowed.
`boolean`	`allowEmptyInPredicate` Whether IN predicate may have an empty value list.
`boolean`	`allowEmptySchemaValuesAsDefaultSchema` If `true` constructs like 'CREATE TABLE CATALOG..TABLE_NAME' are allowed, the default schema is used.
`boolean`	`allowPlusForStringConcat` Text can be concatenated using '+'.
`boolean`	`allowUnrelatedOrderByExpressionsInDistinctQueries` If `true` unrelated ORDER BY expression are allowed in DISTINCT queries, if `false` they are disallowed.
`boolean`	`allowUsingFromClauseInUpdateStatement` If `true`, allow using from clause in update statement.
`boolean`	`alterTableExtensionsMySQL` If `true` some additional non-standard ALTER TABLE commands are allowed.
`boolean`	`alterTableModifyColumn` If `true` non-standard ALTER TABLE MODIFY COLUMN is allowed.
`boolean`	`alterTableModifyColumnPreserveNullability` If `true` non-standard ALTER TABLE MODIFY COLUMN preserves nullability when changing data type.
`boolean`	`autoIncrementClause` Whether MySQL-style AUTO_INCREMENT clause is supported.
`boolean`	`charAndByteLengthUnits` If `true` 'CHAR' and 'BYTE' length units are allowed.
`Mode.CharPadding`	`charPadding` How to pad or trim CHAR values.
`boolean`	`convertOnlyToSmallerScale` When converting the scale of decimal data, the number is only converted if the new scale is smaller than the current scale.
`boolean`	`createUniqueConstraintForReferencedColumns` If `true`, referential constraints will create a unique constraint on referenced columns if it doesn't exist instead of throwing an exception.
`boolean`	`dateIsTimestamp0` Whether DATE data type is parsed as TIMESTAMP(0).
`boolean`	`dateTimeValueWithinTransaction` If `true`, datetime value function return the same value within a transaction, if `false` datetime value functions return the same value within a command.
`boolean`	`decimalSequences` If `true` NEXT VALUE FOR SEQUENCE, CURRENT VALUE FOR SEQUENCE, SEQUENCE.NEXTVAL, and SEQUENCE.CURRVAL return values with DECIMAL/NUMERIC data type instead of BIGINT.
`boolean`	`deleteIdentifierFrom` If `true` DELETE identifier FROM is allowed
`java.util.Set<java.lang.String>`	`disallowedTypes` An optional Set of hidden/disallowed column types.
`boolean`	`discardWithTableHints` Discard SQLServer table hints (e.g.
`Mode.ExpressionNames`	`expressionNames` How column names are generated for expressions.
`boolean`	`forBitData` If `true` 'FOR BIT DATA' clauses are allowed for character string data types.
`boolean`	`greatestLeastIgnoreNulls` If `true` GREATEST and LEAST ignore nulls
`boolean`	`groupByColumnIndex` Allow to use GROUP BY n, where n is column index in the SELECT list, similar to ORDER BY
`boolean`	`identityClause` Whether SQL Server-style IDENTITY clause is supported.
`boolean`	`identityColumnsHaveDefaultOnNull` If `true`, identity columns have DEFAULT ON NULL clause.
`boolean`	`identityDataType` Whether IDENTITY pseudo data type is supported.
`boolean`	`indexDefinitionInCreateTable` Creating indexes in the CREATE TABLE statement is allowed using `INDEX(..)` or `KEY(..)`.
`boolean`	`insertOnConflict` PostgreSQL style INSERT ...
`boolean`	`isolationLevelInSelectOrInsertStatement` can set the isolation level using WITH {RR\|RS\|CS\|UR}
`boolean`	`limit` Whether LIMIT / OFFSET clauses are supported.
`boolean`	`logIsLogBase10` The single-argument function LOG() uses base 10 instead of E.
`boolean`	`mergeWhere` If `true`, merge when matched clause may have WHERE clause.
`boolean`	`minusIsExcept` Whether MINUS can be used as EXCEPT.
`boolean`	`mySqlTableOptions` If `true` MySQL table and column options are allowed
`boolean`	`nextvalAndCurrvalPseudoColumns` If `true`, sequence.NEXTVAL and sequence.CURRVAL pseudo columns are supported.
`boolean`	`nextValueReturnsDifferentValues` If `true`, the next value expression returns different values when invoked multiple times within a row.
`NullsDistinct`	`nullsDistinct` Determines how rows with `NULL` values in indexed columns are handled in unique indexes and constraints by default.
`boolean`	`numericIsDecfloat` Whether NUMERIC and DECIMAL/DEC without parameters are parsed as DECFLOAT.
`boolean`	`numericWithBooleanComparison` Allow to compare numeric with BOOLEAN.
`boolean`	`onDuplicateKeyUpdate` MySQL style INSERT ...
`boolean`	`regexpReplaceBackslashReferences` The function REGEXP_REPLACE() uses \ for back-references.
`boolean`	`replaceInto` MySQL style REPLACE INTO.
`boolean`	`serialDataTypes` Whether SERIAL and BIGSERIAL pseudo data types are supported.
`boolean`	`squareBracketQuotedNames` Identifiers may be quoted using square brackets as in [Test].
`java.util.regex.Pattern`	`supportedClientInfoPropertiesRegEx` Pattern describing the keys the java.sql.Connection.setClientInfo() method accepts.
`boolean`	`supportPoundSymbolForColumnNames` Support the # for column names
`boolean`	`swapConvertFunctionParameters` Swap the parameters of the CONVERT function.
`boolean`	`swapLogFunctionParameters` Swap the parameters of LOG() function.
`boolean`	`sysDummy1` Support the pseudo-table SYSIBM.SYSDUMMY1.
`boolean`	`systemColumns` The system columns 'ctid' and 'oid' are supported.
`boolean`	`takeGeneratedSequenceValue` If `true`, last identity of the session is updated on generation of a new sequence value.
`boolean`	`takeInsertedIdentity` If `true`, last identity of the session is updated on insertion of a new value into identity column.
`boolean`	`topInDML` Whether TOP clause in DML commands is supported.
`boolean`	`topInSelect` Whether TOP clause in SELECT queries is supported.
`boolean`	`treatEmptyStringsAsNull` Empty strings are treated like NULL values.
`boolean`	`truncateTableRestartIdentity` If `true` TRUNCATE TABLE uses RESTART IDENTITY by default.
`java.util.HashMap<java.lang.String,org.h2.value.DataType>`	`typeByNameMap` Custom mappings from type names to data types.
`boolean`	`updateSequenceOnManualIdentityInsertion` If `true`, sequences of generated by default identity columns are updated when value is provided by user.
`Mode.ViewExpressionNames`	`viewExpressionNames` How column names are generated for views.
`boolean`	`zeroExLiteralsAreBinaryStrings` If `true` `0x`-prefixed numbers are parsed as binary string literals, if `false` they are parsed as hexadecimal numeric values.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Mode.ModeEnum`	`getEnum()`
`static Mode`	`getInstance(java.lang.String name)` Get the mode with the given name.
`java.lang.String`	`getName()`
`static Mode`	`getRegular()`
`java.lang.String`	`toString()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - aliasColumnName
```
public boolean aliasColumnName
```
    When enabled, aliased columns (as in SELECT ID AS I FROM TEST) return the alias (I in this case) in ResultSetMetaData.getColumnName() and 'null' in getTableName(). If disabled, the real column name (ID in this case) and table name is returned.
  - convertOnlyToSmallerScale
```
public boolean convertOnlyToSmallerScale
```
    When converting the scale of decimal data, the number is only converted if the new scale is smaller than the current scale. Usually, the scale is converted and 0s are added if required.
  - indexDefinitionInCreateTable
```
public boolean indexDefinitionInCreateTable
```
    Creating indexes in the CREATE TABLE statement is allowed using INDEX(..) or KEY(..). Example: create table test(id int primary key, name varchar(255), key idx_name(name));
  - squareBracketQuotedNames
```
public boolean squareBracketQuotedNames
```
    Identifiers may be quoted using square brackets as in [Test].
  - systemColumns
```
public boolean systemColumns
```
    The system columns 'ctid' and 'oid' are supported.
  - nullsDistinct
```
public NullsDistinct nullsDistinct
```
    Determines how rows with NULL values in indexed columns are handled in unique indexes and constraints by default.
  - treatEmptyStringsAsNull
```
public boolean treatEmptyStringsAsNull
```
    Empty strings are treated like NULL values. Useful for Oracle emulation.
  - greatestLeastIgnoreNulls
```
public boolean greatestLeastIgnoreNulls
```
    If true GREATEST and LEAST ignore nulls
  - sysDummy1
```
public boolean sysDummy1
```
    Support the pseudo-table SYSIBM.SYSDUMMY1.
  - allowPlusForStringConcat
```
public boolean allowPlusForStringConcat
```
    Text can be concatenated using '+'.
  - logIsLogBase10
```
public boolean logIsLogBase10
```
    The single-argument function LOG() uses base 10 instead of E.
  - swapLogFunctionParameters
```
public boolean swapLogFunctionParameters
```
    Swap the parameters of LOG() function.
  - regexpReplaceBackslashReferences
```
public boolean regexpReplaceBackslashReferences
```
    The function REGEXP_REPLACE() uses \ for back-references.
  - swapConvertFunctionParameters
```
public boolean swapConvertFunctionParameters
```
    Swap the parameters of the CONVERT function.
  - isolationLevelInSelectOrInsertStatement
```
public boolean isolationLevelInSelectOrInsertStatement
```
    can set the isolation level using WITH {RR|RS|CS|UR}
  - onDuplicateKeyUpdate
```
public boolean onDuplicateKeyUpdate
```
    MySQL style INSERT ... ON DUPLICATE KEY UPDATE ... and INSERT IGNORE.
  - replaceInto
```
public boolean replaceInto
```
    MySQL style REPLACE INTO.
  - insertOnConflict
```
public boolean insertOnConflict
```
    PostgreSQL style INSERT ... ON CONFLICT DO NOTHING.
  - supportedClientInfoPropertiesRegEx
```
public java.util.regex.Pattern supportedClientInfoPropertiesRegEx
```
    Pattern describing the keys the java.sql.Connection.setClientInfo() method accepts.
  - supportPoundSymbolForColumnNames
```
public boolean supportPoundSymbolForColumnNames
```
    Support the # for column names
  - allowEmptyInPredicate
```
public boolean allowEmptyInPredicate
```
    Whether IN predicate may have an empty value list.
  - charPadding
```
public Mode.CharPadding charPadding
```
    How to pad or trim CHAR values.
  - allowDB2TimestampFormat
```
public boolean allowDB2TimestampFormat
```
    Whether DB2 TIMESTAMP formats are allowed.
  - discardWithTableHints
```
public boolean discardWithTableHints
```
    Discard SQLServer table hints (e.g. "SELECT * FROM table WITH (NOLOCK)")
  - dateTimeValueWithinTransaction
```
public boolean dateTimeValueWithinTransaction
```
    If true, datetime value function return the same value within a transaction, if false datetime value functions return the same value within a command.
  - zeroExLiteralsAreBinaryStrings
```
public boolean zeroExLiteralsAreBinaryStrings
```
    If true 0x-prefixed numbers are parsed as binary string literals, if false they are parsed as hexadecimal numeric values.
  - allowUnrelatedOrderByExpressionsInDistinctQueries
```
public boolean allowUnrelatedOrderByExpressionsInDistinctQueries
```
    If true unrelated ORDER BY expression are allowed in DISTINCT queries, if false they are disallowed.
  - alterTableExtensionsMySQL
```
public boolean alterTableExtensionsMySQL
```
    If true some additional non-standard ALTER TABLE commands are allowed.
  - alterTableModifyColumn
```
public boolean alterTableModifyColumn
```
    If true non-standard ALTER TABLE MODIFY COLUMN is allowed.
  - alterTableModifyColumnPreserveNullability
```
public boolean alterTableModifyColumnPreserveNullability
```
    If true non-standard ALTER TABLE MODIFY COLUMN preserves nullability when changing data type.
  - mySqlTableOptions
```
public boolean mySqlTableOptions
```
    If true MySQL table and column options are allowed
  - deleteIdentifierFrom
```
public boolean deleteIdentifierFrom
```
    If true DELETE identifier FROM is allowed
  - truncateTableRestartIdentity
```
public boolean truncateTableRestartIdentity
```
    If true TRUNCATE TABLE uses RESTART IDENTITY by default.
  - decimalSequences
```
public boolean decimalSequences
```
    If true NEXT VALUE FOR SEQUENCE, CURRENT VALUE FOR SEQUENCE, SEQUENCE.NEXTVAL, and SEQUENCE.CURRVAL return values with DECIMAL/NUMERIC data type instead of BIGINT.
  - allowEmptySchemaValuesAsDefaultSchema
```
public boolean allowEmptySchemaValuesAsDefaultSchema
```
    If true constructs like 'CREATE TABLE CATALOG..TABLE_NAME' are allowed, the default schema is used.
  - allNumericTypesHavePrecision
```
public boolean allNumericTypesHavePrecision
```
    If true all numeric data types may have precision and 'UNSIGNED' clause.
  - forBitData
```
public boolean forBitData
```
    If true 'FOR BIT DATA' clauses are allowed for character string data types.
  - charAndByteLengthUnits
```
public boolean charAndByteLengthUnits
```
    If true 'CHAR' and 'BYTE' length units are allowed.
  - nextvalAndCurrvalPseudoColumns
```
public boolean nextvalAndCurrvalPseudoColumns
```
    If true, sequence.NEXTVAL and sequence.CURRVAL pseudo columns are supported.
  - nextValueReturnsDifferentValues
```
public boolean nextValueReturnsDifferentValues
```
    If true, the next value expression returns different values when invoked multiple times within a row. This setting does not affect NEXTVAL() function.
  - updateSequenceOnManualIdentityInsertion
```
public boolean updateSequenceOnManualIdentityInsertion
```
    If true, sequences of generated by default identity columns are updated when value is provided by user.
  - takeInsertedIdentity
```
public boolean takeInsertedIdentity
```
    If true, last identity of the session is updated on insertion of a new value into identity column.
  - takeGeneratedSequenceValue
```
public boolean takeGeneratedSequenceValue
```
    If true, last identity of the session is updated on generation of a new sequence value.
  - identityColumnsHaveDefaultOnNull
```
public boolean identityColumnsHaveDefaultOnNull
```
    If true, identity columns have DEFAULT ON NULL clause.
  - mergeWhere
```
public boolean mergeWhere
```
    If true, merge when matched clause may have WHERE clause.
  - allowUsingFromClauseInUpdateStatement
```
public boolean allowUsingFromClauseInUpdateStatement
```
    If true, allow using from clause in update statement.
  - createUniqueConstraintForReferencedColumns
```
public boolean createUniqueConstraintForReferencedColumns
```
    If true, referential constraints will create a unique constraint on referenced columns if it doesn't exist instead of throwing an exception.
  - expressionNames
```
public Mode.ExpressionNames expressionNames
```
    How column names are generated for expressions.
  - viewExpressionNames
```
public Mode.ViewExpressionNames viewExpressionNames
```
    How column names are generated for views.
  - topInSelect
```
public boolean topInSelect
```
    Whether TOP clause in SELECT queries is supported.
  - topInDML
```
public boolean topInDML
```
    Whether TOP clause in DML commands is supported.
  - limit
```
public boolean limit
```
    Whether LIMIT / OFFSET clauses are supported.
  - minusIsExcept
```
public boolean minusIsExcept
```
    Whether MINUS can be used as EXCEPT.
  - identityDataType
```
public boolean identityDataType
```
    Whether IDENTITY pseudo data type is supported.
  - serialDataTypes
```
public boolean serialDataTypes
```
    Whether SERIAL and BIGSERIAL pseudo data types are supported.
  - identityClause
```
public boolean identityClause
```
    Whether SQL Server-style IDENTITY clause is supported.
  - autoIncrementClause
```
public boolean autoIncrementClause
```
    Whether MySQL-style AUTO_INCREMENT clause is supported.
  - dateIsTimestamp0
```
public boolean dateIsTimestamp0
```
    Whether DATE data type is parsed as TIMESTAMP(0).
  - numericIsDecfloat
```
public boolean numericIsDecfloat
```
    Whether NUMERIC and DECIMAL/DEC without parameters are parsed as DECFLOAT.
  - disallowedTypes
```
public java.util.Set<java.lang.String> disallowedTypes
```
    An optional Set of hidden/disallowed column types. Certain DBMSs don't support all column types provided by H2, such as "NUMBER" when using PostgreSQL mode.
  - typeByNameMap
```
public java.util.HashMap<java.lang.String,org.h2.value.DataType> typeByNameMap
```
    Custom mappings from type names to data types.
  - groupByColumnIndex
```
public boolean groupByColumnIndex
```
    Allow to use GROUP BY n, where n is column index in the SELECT list, similar to ORDER BY
  - numericWithBooleanComparison
```
public boolean numericWithBooleanComparison
```
    Allow to compare numeric with BOOLEAN.
  - acceptsCommaAsJsonKeyValueSeparator
```
public boolean acceptsCommaAsJsonKeyValueSeparator
```
    Accepts comma ',' as key/value separator in JSON_OBJECT and JSON_OBJECTAGG functions.
- Method Detail
  - getInstance
```
public static Mode getInstance(java.lang.String name)
```
    Get the mode with the given name.
    
    Parameters:
    
    name - the name of the mode
    
    Returns:
    
    the mode object
  - getRegular
```
public static Mode getRegular()
```
  - getName
```
public java.lang.String getName()
```
  - getEnum
```
public Mode.ModeEnum getEnum()
```
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class Mode

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

aliasColumnName

convertOnlyToSmallerScale

indexDefinitionInCreateTable

squareBracketQuotedNames

systemColumns

nullsDistinct

treatEmptyStringsAsNull

greatestLeastIgnoreNulls

sysDummy1

allowPlusForStringConcat

logIsLogBase10

swapLogFunctionParameters

regexpReplaceBackslashReferences

swapConvertFunctionParameters

isolationLevelInSelectOrInsertStatement

onDuplicateKeyUpdate

replaceInto

insertOnConflict

supportedClientInfoPropertiesRegEx

supportPoundSymbolForColumnNames

allowEmptyInPredicate

charPadding

allowDB2TimestampFormat

discardWithTableHints

dateTimeValueWithinTransaction

zeroExLiteralsAreBinaryStrings

allowUnrelatedOrderByExpressionsInDistinctQueries

alterTableExtensionsMySQL

alterTableModifyColumn

alterTableModifyColumnPreserveNullability

mySqlTableOptions

deleteIdentifierFrom

truncateTableRestartIdentity

decimalSequences

allowEmptySchemaValuesAsDefaultSchema

allNumericTypesHavePrecision

forBitData

charAndByteLengthUnits

nextvalAndCurrvalPseudoColumns

nextValueReturnsDifferentValues

updateSequenceOnManualIdentityInsertion

takeInsertedIdentity

takeGeneratedSequenceValue

identityColumnsHaveDefaultOnNull

mergeWhere

allowUsingFromClauseInUpdateStatement

createUniqueConstraintForReferencedColumns

expressionNames

viewExpressionNames

topInSelect

topInDML

limit

minusIsExcept

identityDataType

serialDataTypes

identityClause

autoIncrementClause

dateIsTimestamp0

numericIsDecfloat

disallowedTypes

typeByNameMap

groupByColumnIndex

numericWithBooleanComparison

acceptsCommaAsJsonKeyValueSeparator

Method Detail

getInstance

getRegular

getName

getEnum

toString