SERIAL CONSISTENCY
Sets the serial consistency for lightweight transactions (LWTs). A LWT contains an IF EXISTS or IF NOT EXISTS clause. See Data consistency in the documentation.
When using a LWT:
-
Levels must be set for SERIAL CONSISTENCY and CONSISTENCY.
-
SERIAL CONSISTENCY can be set to SERIAL or LOCAL_SERIAL.
-
CONSISTENCY cannot be set to SERIAL or LOCAL_SERIAL.
To set the consistency level for non-LWTs, use the CONSISTENCY command. |
Synopsis
SERIAL CONSISTENCY [ <consistency_level> ]
Syntax legend
Syntax conventions | Description |
---|---|
UPPERCASE |
Literal keyword. |
Lowercase |
Not literal. |
|
Variable value. Replace with a user-defined value. |
|
Optional.
Square brackets ( |
|
Group.
Parentheses ( |
|
Or.
A vertical bar ( |
|
Repeatable.
An ellipsis ( |
|
Single quotation ( |
|
Map collection.
Braces ( |
Set, list, map, or tuple.
Angle brackets ( |
|
|
End CQL statement.
A semicolon ( |
|
Separate the command line options from the command arguments with two hyphens ( |
|
Search CQL only: Single quotation marks ( |
|
Search CQL only: Identify the entity and literal value to overwrite the XML element in the schema and solrConfig files. |
- consistency_level
-
Consistency level. Can be set to
SERIAL
orLOCAL_SERIAL
.
Examples
Show the current SERIAL CONSISTENCY
status:
SERIAL CONSISTENCY
Reports the current setting:
Current serial consistency level set to SERIAL.
Set the serial consistency level with a value:
SERIAL CONSISTENCY LOCAL_SERIAL
Confirms the level is set:
Serial consistency level set to LOCAL_SERIAL.
You can use the TRACE command to examine the difference between |
When using a LWT, you must have levels set for CONSISTENCY and SERIAL CONSISTENCY.
For example, write data using a LWT with IF NOT EXISTS to examine if the row already exists before performing the write:
CONSISTENCY ONE
SERIAL CONSISTENCY SERIAL
INSERT INTO cycling.cyclist_name (
id, firstname, lastname
) VALUES (
e7ae5cf3-d358-4d99-b900-85902fda9bb0, 'Alex', 'FRAME'
)
IF NOT EXISTS;
If the record already exists then the write is not applied, as shown in the following result:
[applied] | id | firstname | lastname
-----------+--------------------------------------+-----------+----------
False | e7ae5cf3-d358-4d99-b900-85902fda9bb0 | Alex | FRAME