[TDR Generic Table] [MySQL Protocol Compatibility Interface] Update Records

1. Interface Description

Update existing records to a specified table.

2. Preparations

Refer to Preparation document, create mysql_table table, and use MySQL Client to connect to TcaplusDB successfully.

3. Syntax Rules of WHERE Clause of Update Statement

The WHERE clause of update statement consists of two parts: (1) required part: index or primarykey; (2) optional part: filter conditions.

The fields in indexor primarykey can only be queried equivalently, and the fields that make up index or primarykey can only be connected by the operator AND;

Filter conditions support NOT, =, >, <, !=, >= and <=. Multiple filter conditions can be connected with AND or OR, and support to filter key fields, value fields, version fields, and TTL fields.

  1. When using primarykey to update data to mysql_table, the WHEREclause form is as follows:
WHERE k1=1 AND k2=2 AND k3='one';
  1. When using primarykey + filter condition to update data to mysql_table, the WHERE clause form is as follows: (if the filter condition contains OR operator, the filter condition must be bracketed):
WHERE k1=1 AND k2=2 AND k3='one' AND (Filter condition);
  1. When using index to update data to mysql_table, the WHEREclause form is as follows:
WHERE k1=1 AND k2=2;

Note: When using index to update data, multiple records may be updated at one time.

4. SQL Examples

  1. When using primarykey to update a record to mysql_table, the SQL statement has the following two forms:
UPDATE mysql_table SET v1=v1+1, v2=2 WHERE k1=1 AND k2=2 AND k3='one';
UPDATE mysql_table SET v1=v1-1, v2=2 WHERE k1=1 AND k2=2 AND k3='one' AND (v1>=4 OR v2<=4);

The content in the brackets of the 2nd SQL statement above is the filter condition.

  1. When using primarykey to update multiple records to mysql_table in batches, the SQL statement is as follows:
UPDATE mysql_table SET v1=v1-1, v2=v2+2 WHERE k1=1 AND k2=2 AND k3='one' OR k1=1 AND k2=2 AND k3='two' AND (v1>=4 OR v2<=4);

The content in the brackets of the SQL statement above is the filter condition.

  1. When using index to update multiple records to mysql_table in batches, the SQL statement is as follows:
UPDATE mysql_table SET v1=v1+1, v2=2 WHERE k1=1 AND k2=2;

Filter conditions are not supported when using index to update records.

5. FAQ

For details, see Meaning and Handling of Error Codes.

6. Other Reference Documents

[TDR Generic Table] [C++ SDK] Interface Description for Updating a Record

[TDR Generic Table] [Java SDK] Interface Description for Updating a Record

[TDR Generic Table][Go SDK] Interface Description for Updating a Record

[TDR Generic Table][C++ SDK] Interface Description for Auto-increment of Fields.

[TDR Generic Table] [Java SDK] Interface Description for Auto-increment of Part Fields in a Record.

[TDR Generic Table] [Java SDK] Interface Description for Auto-increment of Part Fields.

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