DBZ-7362 Support DECFLOAT in Db2 connector #129
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Welcome as a new contributor to Debezium, @leoloel. Reviewers, please add missing author name(s) and alias name(s) to the COPYRIGHT.txt and Aliases.txt respectively. |
| @@ -52,6 +52,10 @@ public SchemaBuilder schemaBuilder(Column column) { | |||
| case Types.TINYINT: | |||
| // values are an 8-bit unsigned integer value between 0 and 255, we thus need to store it in short int | |||
| return SchemaBuilder.int16(); | |||
| case Types.OTHER: | |||
| if (matches(column.typeName().toUpperCase(), "DECFLOAT")) { | |||
| return SchemaBuilder.float64(); | |||
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What is the real datatype coming from the database? It seems to me according to docs that it is either 16 or 32 bit signed floating point decimal. How does it differ from REAL/FLOAT? Does it makes sense to map it to either FLOAT32 or FLOAT64 based on the value? What Java class is returned by the JDBC driver when small and large DECFLOATs are used?
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The range of a decimal floating point number is either 16 or 34 digits of precision. You can refer to this manual. https://www.ibm.com/docs/en/db2-for-zos/12?topic=numbers-decimal-floating-point-decfloat
Create table like this,
create table TEST.T1
(
ID INTEGER not null primary key,
C_DECFLOAT DECFLOAT(34)
);
Then insert a record, INSERT INTO TEST.T1 (ID, C_DECFLOAT) VALUES (1, DECFLOAT(1.234));
Finally execute the select statement，select C_DECFLOAT from TEST.T1. The result is 1.234, without padding the 0's at the end.
To be honest, I don’t quite understand the difference between decfloat and float types.
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Db2OnlineDefaultValueIT>AbstractDb2DefaultValueIT.shouldHandleDateTimeDefaultTypes:201->AbstractDb2DefaultValueIT.shouldHandleDefaultValuesCommon:215->AbstractDb2DefaultValueIT.testDefaultValuesAlterTableAdd:491->AbstractDb2DefaultValueIT.assertSchemaFieldWithDefaultCurrentDate:542->AbstractDb2DefaultValueIT.assertSchemaFieldValueWithDefault:538->AbstractDb2DefaultValueIT.lambda$assertSchemaFieldWithDefaultCurrentDate$2:550 [Unexpected field value: AVAL_DATE_SYSDATE_NONNULL] I tested this test locally and the result was successful. I don’t know why the check that |
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@leoloel DECFLOAT seems to be precise numeric type similar to Could you please give the PR look if it is OK for you? If yes I am going to mege it after CI excution. In that case would you be willing to send a PR with Db2 docs update for this datatype mapping? |
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Test failures are unrelated. |
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ok, I will try it. |
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Why not reuse the convertDecimal function? I think the contents of convertDecimal and convertDecfloat are the same.
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Hi, it is not. This is taken form PostgreSQL to hadnle potential issue with trailing zeroes. We don't know if it is problem here but it is kind of defensive measure.
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Could you please check this pr? debezium/debezium#5189
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