Data Pipeline SQL Compatibility for TiDB Cloud Lake
This document describes the DDL, DML, and column type support for TiDB Cloud Data Pipeline when replicating data to TiDB Cloud Lake. Use it to plan your pipeline, validate schema compatibility, or troubleshoot type conversions.
Note
Supported behavior depends on the TiCDC and TiDB Cloud Lake versions in use. If you observe different behavior, contact TiDB Cloud Support.
DDL support summary
DDL operation
Status
Notes
CREATE TABLE
✅
ADD COLUMN
✅
ADD COLUMN ... NOT NULL DEFAULT ...
✅
DROP COLUMN
✅
RENAME COLUMN
✅
MODIFY COLUMN
⚠️ Partial support
Supported only for the schema-evolution cases listed below. Other conversions are not guaranteed and can block downstream consumption.
Supported MODIFY COLUMN conversions
From
To
Notes
VARCHAR
TEXT
Common widening conversion during schema evolution.
TINYINT
INT
Promotes integer storage width.
INT
BIGINT
Common widening conversion during schema evolution.
INT
VARCHAR / TEXT
Used when the target type is converted to a string representation.
DDL operations not listed here are not processed by the pipeline and might block subsequent consumption for the affected table. In addition, combining multiple changes in a single ALTER TABLE statement is not supported.
DML support summary
DML operation
Status
INSERT
✅
UPDATE
✅
DELETE
✅
DML operations not listed here are not propagated to the destination.
Type mapping reference
Integer types
TiDB type
TiDB Cloud Lake type
TINYINT
INT8
TINYINT UNSIGNED
UINT8
SMALLINT
INT16
SMALLINT UNSIGNED
UINT16
MEDIUMINT
INT32
INT / INTEGER
INT32
MEDIUMINT UNSIGNED / INT UNSIGNED / INTEGER UNSIGNED
UINT32
BIGINT
INT64
BIGINT UNSIGNED
UINT64
Floating-point types
TiDB type
TiDB Cloud Lake type
FLOAT
FLOAT32
DOUBLE / REAL
FLOAT64
Exact numeric types
TiDB type
TiDB Cloud Lake type
Notes
DECIMAL(P,S)
DECIMAL(P,S)
Precision and scale are preserved exactly. The same applies to NUMERIC(P,S).
DECIMAL (no precision)
DECIMAL(76,30)
Automatically widened to the maximum valid precision to avoid silent truncation.
NUMERIC (no precision)
DECIMAL(76,30)
Same as above.
Date and time types
TiDB type
TiDB Cloud Lake type
Notes
DATE
DATE
DATETIME / DATETIME(n)
TIMESTAMP
Fractional-second precision is supported.
TIMESTAMP / TIMESTAMP(n)
TIMESTAMP
Fractional-second precision is supported.
TIME
VARCHAR
TiDB Cloud Lake has no standalone TIME type, so it is stored as text.
YEAR
INT16
Mapped as an integer, not a temporal type.
String types
TiDB type
TiDB Cloud Lake type
Notes
CHAR / VARCHAR
VARCHAR
Length is not preserved.
TINYTEXT / TEXT / MEDIUMTEXT / LONGTEXT
VARCHAR
ENUM
VARCHAR
Requires a content-compatible=true changefeed to preserve the enum text.
SET
VARCHAR
Requires a content-compatible=true changefeed to preserve the element text.
Binary types
TiDB type
TiDB Cloud Lake type
BINARY / VARBINARY
BINARY
TINYBLOB / BLOB / MEDIUMBLOB / LONGBLOB
BINARY
Other types
TiDB type
TiDB Cloud Lake type
Notes
BOOLEAN / BOOL
BOOLEAN
BIT
UINT64
Always mapped as unsigned. All-ones BIT(64) exceeds the signed INT64 range.