"alterTable"
JSON DB "alterTable" action modifies an existing table
The "alterTable" action alters, changes, modifies, updates, or configures an existing table in a database. This action works for all FairCom products that include the FairCom database engine.
Important
Altering a table can break applications that use the table. Be sure to update all applications when you make the change.
"alterTable"temporarily blocks the table. Blocking the table has no effect on the JSON and SQL APIs. It may cause errors 798 or 799 to occur in applications that have opened the table using the ISAM and CTDB APIs.Renaming a table or field causes errors to occur in processes that use the old names.
Changing a field's data type may cause errors in applications that read and write data to that field.
Request examples
Add fields request
This example uses "alterTable" to define new fields of a table.
{
"api": "db",
"authToken": "replaceWithAuthtokenFromCreateSession",
"action": "alterTable",
"params": {
"tableName": "test1",
"addFields": [
{
"name": "rename_me1",
"type": "varchar",
"length": 10,
"nullable": false
},
{
"name": "rename_me2",
"type": "varchar",
"length": 10,
"nullable": false
},
{
"name": "alter_me1",
"type": "varchar",
"length": 10,
"nullable": false
},
{
"name": "alter_me2",
"type": "varchar",
"length": 10,
"nullable": false
},
{
"name": "delete_me1",
"type": "varchar",
"length": 10,
"nullable": false
},
{
"name": "delete_me2",
"type": "varchar",
"length": 10,
"nullable": false
}
]
}
}
This example uses "alterTable" to modify existing fields of a table. Specifically, it changes the name of the "rename_me1" field, to "description" and changes the "length" value of the "alter_me1" field from 10 to 50 and the "nullable" value from false to true.
{
"api": "db",
"authToken": "replaceWithAuthtokenFromCreateSession",
"action": "alterTable",
"params": {
"databaseName": "ctreeSQL",
"ownerName": "admin",
"tableName": "test1",
"alterFields": [
{
"name": "rename_me1",
"type": "varchar",
"newName": "description"
},
{
"name": "alter_me1",
"type": "varchar",
"length": 50,
"nullable": true
}
]
},
"requestId": "2"
}
This example uses "alterTable" to remove the "delete_me1" field.
{
"requestId": "3",
"authToken": "replaceWithAuthtokenFromCreateSession",
"api": "db",
"action": "alterTable",
"params": {
"databaseName": "ctreeSQL",
"ownerName": "admin",
"tableName": "test1",
"deleteFields": [
"delete_me1"
]
}
}
{
"api": "db",
"apiVersion": "1.0",
"requestId": "4",
"authToken": "replaceWithAuthtokenFromCreateSession",
"action": "alterTable",
"params": {
"databaseName": "ctreeSQL",
"ownerName": "admin",
"tableName": "test1",
"transactionModel": "logTransactions"
}
}
{
"api": "db",
"action": "alterTable",
"params": {
"ownerName": "admin",
"tableName": "test1",
"addFields": [
{
"name": "nested_json_object_or_array",
"type": "json",
"length": 65500
},
{
"name": "boolean_byte",
"type": "bit"
},
{
"name": "signed_int8",
"type": "tinyint"
},
{
"name": "signed_int16",
"type": "smallint"
},
{
"name": "signed_int32",
"type": "integer"
},
{
"name": "signed_int64",
"type": "bigint"
},
{
"name": "iee_base2float32",
"type": "real"
},
{
"name": "iee_base2float64",
"type": "float"
},
{
"name": "signed32digits_base10_left32right0",
"type": "number",
"length": 32,
"scale": 0
},
{
"name": "signed32digits_base10_left0right32",
"type": "number",
"length": 32,
"scale": 32
},
{
"name": "signed32digits_base10_left20right12",
"type": "number",
"length": 32,
"scale": 12
},
{
"name": "signed32digits_base10_left30right2",
"type": "money",
"length": 32,
"scale": 2
},
{
"name": "signed32digits_base10_left28right4",
"type": "money",
"length": 32,
"scale": 4
},
{
"name": "date_yyyymmdd",
"type": "date"
},
{
"name": "time_hhmmss",
"type": "time"
},
{
"name": "datetime_yyyymmddthhmmss_nnnz",
"type": "timestamp"
},
{
"name": "fixed_string_10bytes",
"type": "char",
"length": 10
},
{
"name": "variable_string_up_to_max65500bytes",
"type": "varchar",
"length": 65500
},
{
"name": "variable_string_up_to_2GB",
"type": "lvarbinary"
},
{
"name": "fixed_binary_10bytes",
"type": "binary",
"length": 10
},
{
"name": "variable_binary_up_to_max65500bytes",
"type": "varbinary",
"length": 65500
}
],
"alterFields": [
{
"name": "alter_me2",
"type": "varchar",
"length": 50,
"nullable": true
},
{
"name": "datetime_yyyymmddthhmmssfff",
"autoValue": "timestampOnUpdateAndInsert"
}
],
"deleteFields": [
"delete_me2"
],
"transactionModel": "logTransactions",
"growthExtent": 100000,
"padValue": 0,
"fieldDelimiterValue": 0,
"createRecByteIndex": false,
"tableFileExtension": ".dat",
"indexFileExtension": ".idx"
},
"responseOptions": {
"binaryFormat": "hex",
"dataFormat": "objects",
"numberFormat": "string"
},
"authToken": "replaceWithAuthTokenFromCreateSession",
"apiVersion": "1.0",
"requestId": "5",
"debug": "max"
}
{
"authToken": "authToken",
"result": {
"dataFormat": "objects",
"data": [
{
"changeIdField": "changeId",
"createRecByteIndex": false,
"databaseName": "ctreeSQL",
"fieldDelimiterValue": 0,
"fields": [
{
"autoValue": "incrementOnInsert",
"defaultValue": null,
"length": null,
"name": "id",
"nullable": false,
"primaryKey": 1,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "changeid",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "name",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "rename_me1",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "rename_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "alter_me1",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "alter_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "delete_me1",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "delete_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
}
],
"folder": ".\\ctreeSQL.dbs",
"growthExtent": 0,
"indexFileExtension": ".idx",
"indexes": [
{
"collectStats": false,
"compression": "off",
"conditionalExpression": null,
"databaseName": "ctreeSQL",
"deferIndexing": false,
"fields": [
{
"caseInsensitive": false,
"name": "id",
"reverseCompare": false,
"sortDescending": false
}
],
"filename": "admin_test1.idx",
"immutableKeys": false,
"indexName": "id_pk",
"indexNumber": 0,
"ownerName": "admin",
"tableName": "test1",
"unique": true
}
],
"ownerName": "admin",
"padValue": 0,
"path": ".\\ctreeSQL.dbs\\admin_test1.dat",
"primaryKeyFields": [
"id"
],
"smallFile": false,
"tableFileExtension": ".dat",
"tableName": "test1",
"totalRecordCount": 12,
"transactionModel": "logTransactions",
"uid": 1181
}
]
},
"errorCode": 0,
"errorMessage": ""
}
{
"authToken": "authToken",
"result": {
"dataFormat": "objects",
"data": [
{
"changeIdField": "changeId",
"createRecByteIndex": false,
"databaseName": "ctreeSQL",
"fieldDelimiterValue": 0,
"fields": [
{
"autoValue": "incrementOnInsert",
"defaultValue": null,
"length": null,
"name": "id",
"nullable": false,
"primaryKey": 1,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "changeid",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "name",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "description",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "rename_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "alter_me1",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "alter_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "delete_me1",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "delete_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
}
],
"folder": ".\\ctreeSQL.dbs",
"growthExtent": 0,
"indexFileExtension": ".idx",
"indexes": [
{
"collectStats": false,
"compression": "off",
"conditionalExpression": null,
"databaseName": "ctreeSQL",
"deferIndexing": false,
"fields": [
{
"caseInsensitive": false,
"name": "id",
"reverseCompare": false,
"sortDescending": false
}
],
"filename": "admin_test1.idx",
"immutableKeys": false,
"indexName": "id_pk",
"indexNumber": 0,
"ownerName": "admin",
"tableName": "test1",
"unique": true
}
],
"ownerName": "admin",
"padValue": 0,
"path": ".\\ctreeSQL.dbs\\admin_test1.dat",
"primaryKeyFields": [
"id"
],
"smallFile": false,
"tableFileExtension": ".dat",
"tableName": "test1",
"totalRecordCount": 12,
"transactionModel": "logTransactions",
"uid": 1181
}
]
},
"requestId": "2",
"errorCode": 0,
"errorMessage": ""
}
{
"authToken": "authToken",
"result": {
"dataFormat": "objects",
"data": [
{
"changeIdField": "changeId",
"createRecByteIndex": false,
"databaseName": "ctreeSQL",
"fieldDelimiterValue": 0,
"fields": [
{
"autoValue": "incrementOnInsert",
"defaultValue": null,
"length": null,
"name": "id",
"nullable": false,
"primaryKey": 1,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "changeid",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "name",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "description",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "rename_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "alter_me1",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "alter_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "delete_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
}
],
"folder": ".\\ctreeSQL.dbs",
"growthExtent": 0,
"indexFileExtension": ".idx",
"indexes": [
{
"collectStats": false,
"compression": "off",
"conditionalExpression": null,
"databaseName": "ctreeSQL",
"deferIndexing": false,
"fields": [
{
"caseInsensitive": false,
"name": "id",
"reverseCompare": false,
"sortDescending": false
}
],
"filename": "admin_test1.idx",
"immutableKeys": false,
"indexName": "id_pk",
"indexNumber": 0,
"ownerName": "admin",
"tableName": "test1",
"unique": true
}
],
"ownerName": "admin",
"padValue": 0,
"path": ".\\ctreeSQL.dbs\\admin_test1.dat",
"primaryKeyFields": [
"id"
],
"smallFile": false,
"tableFileExtension": ".dat",
"tableName": "test1",
"totalRecordCount": 12,
"transactionModel": "logTransactions",
"uid": 1181
}
]
},
"requestId": "3",
"errorCode": 0,
"errorMessage": ""
}
{
"authToken": "authToken",
"result": {
"dataFormat": "objects",
"data": [
{
"changeIdField": "changeId",
"createRecByteIndex": false,
"databaseName": "ctreeSQL",
"fieldDelimiterValue": 0,
"fields": [
{
"autoValue": "incrementOnInsert",
"defaultValue": null,
"length": null,
"name": "id",
"nullable": false,
"primaryKey": 1,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "changeid",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "name",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "description",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "rename_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "alter_me1",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "alter_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "delete_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
}
],
"folder": ".\\ctreeSQL.dbs",
"growthExtent": 0,
"indexFileExtension": ".idx",
"indexes": [
{
"collectStats": false,
"compression": "off",
"conditionalExpression": null,
"databaseName": "ctreeSQL",
"deferIndexing": false,
"fields": [
{
"caseInsensitive": false,
"name": "id",
"reverseCompare": false,
"sortDescending": false
}
],
"filename": "admin_test1.idx",
"immutableKeys": false,
"indexName": "id_pk",
"indexNumber": 0,
"ownerName": "admin",
"tableName": "test1",
"unique": true
}
],
"ownerName": "admin",
"padValue": 0,
"path": ".\\ctreeSQL.dbs\\admin_test1.dat",
"primaryKeyFields": [
"id"
],
"smallFile": false,
"tableFileExtension": ".dat",
"tableName": "test1",
"totalRecordCount": 12,
"transactionModel": "logTransactions",
"uid": 1181
}
]
},
"requestId": "4",
"errorCode": 0,
"errorMessage": ""
}
{
"authToken": "authToken",
"result": {
"dataFormat": "objects",
"data": [
{
"changeIdField": "changeId",
"createRecByteIndex": false,
"databaseName": "ctreeSQL",
"fieldDelimiterValue": 0,
"fields": [
{
"autoValue": "incrementOnInsert",
"defaultValue": null,
"length": null,
"name": "id",
"nullable": false,
"primaryKey": 1,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "changeid",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "name",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "description",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "rename_me2",
"nullable": false,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "alter_me1",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 50,
"name": "alter_me2",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 65500,
"name": "nested_json_object_or_array",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "json"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "boolean_byte",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bit"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "signed_int8",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "tinyint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "signed_int16",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "smallint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "signed_int32",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "integer"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "signed_int64",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "bigint"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "ieee_base2float32",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "real"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "ieee_base2float64",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "float"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 32,
"name": "signed32digits_base10_left32right0",
"nullable": true,
"primaryKey": 0,
"scale": 0,
"type": "number"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 32,
"name": "signed32digits_base10_left0right32",
"nullable": true,
"primaryKey": 0,
"scale": 32,
"type": "number"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 32,
"name": "signed32digits_base10_left20right12",
"nullable": true,
"primaryKey": 0,
"scale": 12,
"type": "number"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 32,
"name": "signed32digits_base10_left30right2",
"nullable": true,
"primaryKey": 0,
"scale": 2,
"type": "money"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 32,
"name": "signed32digits_base10_left28right4",
"nullable": true,
"primaryKey": 0,
"scale": 4,
"type": "money"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "date_yyyymmdd",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "date"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "time_hhmmss",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "time"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "datetime_yyyymmddthhmmss_nnnz",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "timestamp"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "fixed_string_10bytes",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "char"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 65500,
"name": "variable_string_up_to_max65500bytes",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "variable_string_up_to_2gb",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "lvarchar"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 10,
"name": "fixed_binary_10bytes",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "binary"
},
{
"autoValue": "none",
"defaultValue": null,
"length": 65500,
"name": "variable_binary_up_to_max65500bytes",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "varbinary"
},
{
"autoValue": "none",
"defaultValue": null,
"length": null,
"name": "variable_binary_up_to_2gb",
"nullable": true,
"primaryKey": 0,
"scale": null,
"type": "lvarbinary"
}
],
"folder": ".\\ctreeSQL.dbs",
"growthExtent": 100000,
"indexFileExtension": ".idx",
"indexes": [
{
"collectStats": false,
"compression": "off",
"conditionalExpression": null,
"databaseName": "ctreeSQL",
"deferIndexing": false,
"fields": [
{
"caseInsensitive": false,
"name": "id",
"reverseCompare": false,
"sortDescending": false
}
],
"filename": "admin_test1.idx",
"immutableKeys": false,
"indexName": "id_pk",
"indexNumber": 0,
"ownerName": "admin",
"tableName": "test1",
"unique": true
}
],
"ownerName": "admin",
"padValue": 0,
"path": ".\\ctreeSQL.dbs\\admin_test1.dat",
"primaryKeyFields": [
"id"
],
"smallFile": false,
"tableFileExtension": ".dat",
"tableName": "test1",
"totalRecordCount": 12,
"transactionModel": "logTransactions",
"uid": 1181
}
]
},
"requestId": "5",
"debugInfo": {
"request": {
"authToken": "authToken",
"api": "db",
"action": "alterTable",
"params": {
"databaseName": "ctreeSQL",
"ownerName": "admin",
"tableName": "test1",
"addFields": [
{
"name": "nested_json_object_or_array",
"type": "json",
"length": 65500
},
{
"name": "boolean_byte",
"type": "bit"
},
{
"name": "signed_int8",
"type": "tinyint"
},
{
"name": "signed_int16",
"type": "smallint"
},
{
"name": "signed_int32",
"type": "integer"
},
{
"name": "signed_int64",
"type": "bigint"
},
{
"name": "ieee_base2float32",
"type": "real"
},
{
"name": "ieee_base2float64",
"type": "float"
},
{
"name": "signed32digits_base10_left32right0",
"type": "number",
"length": 32,
"scale": 0
},
{
"name": "signed32digits_base10_left0right32",
"type": "number",
"length": 32,
"scale": 32
},
{
"name": "signed32digits_base10_left20right12",
"type": "number",
"length": 32,
"scale": 12
},
{
"name": "signed32digits_base10_left30right2",
"type": "money",
"length": 32,
"scale": 2
},
{
"name": "signed32digits_base10_left28right4",
"type": "money",
"length": 32,
"scale": 4
},
{
"name": "date_yyyymmdd",
"type": "date"
},
{
"name": "time_hhmmss",
"type": "time"
},
{
"name": "datetime_yyyymmddthhmmss_nnnz",
"type": "timestamp"
},
{
"name": "fixed_string_10bytes",
"type": "char",
"length": 10
},
{
"name": "variable_string_up_to_max65500bytes",
"type": "varchar",
"length": 65500
},
{
"name": "variable_string_up_to_2GB",
"type": "lvarchar"
},
{
"name": "fixed_binary_10bytes",
"type": "binary",
"length": 10
},
{
"name": "variable_binary_up_to_max65500bytes",
"type": "varbinary",
"length": 65500
},
{
"name": "variable_binary_up_to_2GB",
"type": "lvarbinary"
}
],
"alterFields": [
{
"name": "alter_me2",
"type": "varchar",
"length": 50,
"nullable": true
}
],
"deleteFields": [
"delete_me2"
],
"transactionModel": "logTransactions",
"growthExtent": 100000,
"padValue": 0,
"fieldDelimiterValue": 0,
"createRecByteIndex": false,
"tableFileExtension": ".dat",
"indexFileExtension": ".idx"
},
"apiVersion": "1.0",
"requestId": "5",
"responseOptions": {
"binaryFormat": "hex",
"dataFormat": "objects",
"numberFormat": "string"
},
"debug": "max"
},
"serverSuppliedValues": {
"databaseName": "ctreeSQL",
"ownerName": "admin"
},
"errorData": {
"errorData": null
},
"warnings": []
},
"errorCode": 0,
"errorMessage": ""
}
Use the alterTable JSON API action to alter an existing table in a database
The "params" property is an object that contains an action's parameters. Each action defines its own required and optional properties.
Properties summary
"params" properties summaryProperty | Description | Default | Type | Limits (inclusive) | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
adds new fields to the table and specifies their properties |
| array of objects | |||||||||||||||||||||||
| controls when and how the server automatically sets the field value |
| string |
| |||||||||||||||||||||
| specifies the length of a field's value in a record |
| integer |
| |||||||||||||||||||||
| specifies the name of an existing field in a table | required | string | 0 to 64 bytes | |||||||||||||||||||||
| allows a field to contain a |
| Boolean |
| |||||||||||||||||||||
| specifies the number of places to the right of the decimal point |
| integer |
| |||||||||||||||||||||
| the type of field | required | string |
| |||||||||||||||||||||
alterFields | defines how to alter a field in a table |
| array of objects | ||||||||||||||||||||||
specifies the field name used for change-tracking. |
| string | 1 to 64 bytes | ||||||||||||||||||||||
creates a special index for quickly walking variable-length records backward when |
| Boolean |
| ||||||||||||||||||||||
specifies the name of a database | Defaults to the | string | 1 to 64 bytes | ||||||||||||||||||||||
contains the names of fields to remove from a table |
| array | 1 to 64 bytes | ||||||||||||||||||||||
delimits fields internally for FairCom use |
| integer |
| ||||||||||||||||||||||
specifies the number of bytes that a server uses to extend a file by using a larger number to minimize the number of times a file needs to be extended or using a smaller number to minimize the amount of unused space in a file |
| integer |
| ||||||||||||||||||||||
specifies the file system extension (must contain the dot before the extension) to use for a table's index files |
| string | 0 to 64 bytes | ||||||||||||||||||||||
specifies the unique name of a schema in a database |
| string | 0 to 64 bytes | ||||||||||||||||||||||
pads all |
| integer |
| ||||||||||||||||||||||
specifies the fields to use for the table’s primary key |
| array of strings |
| ||||||||||||||||||||||
tableFileExtension | specifies the file extension (must contain the dot before the extension) that the server assigns to the table's data file on the file system |
| string | 0 to 64 bytes | |||||||||||||||||||||
specifies the name of a table | Required - No default value | string | 1 to 64 bytes | ||||||||||||||||||||||
specifies how the server processes transactions for a table |
| string |
|
The "addFields" property is optional. It allows you to add new fields to the table and specify their properties.
Example
"addFields":
[
{
"name": "myFieldName",
"type": "VARCHAR",
"length": 128,
"scale": 0,
"nullable": true
}
]This property controls when and how the server automatically sets the field value.
Specify only one of these values per field.
"none"indicates the server does not automatically set the field's value."incrementOnInsert"indicates the server automatically increments a field’s value each time the server inserts a new record. It applies to fields that are of the type of decimal or one of the integer types, such as"bigint". Only one field per table can have this attribute. The server returns an error when assigning this attribute to multiple fields. The JSON DB API automatically creates the"id"field as an"incrementOnInsert"field. If you apply this attribute to another field, it becomes the only automatically incremented field in the table. If you want that field to be the primary key, assign"primaryKey": 1to it."timestampOnInsert"indicates the server automatically sets a field’s value to the current date and time of an insert. It applies only to fields with a type of"timestamp"."timestampOnUpdate"indicates the server automatically sets a field’s value to the current date and time of an update. It applies only to timestamp fields."timestampOnUpdateAndInsert"indicates the server automatically sets a field’s value to the current date and time of an insert and an update. It applies only to fields with a type of"timestamp"."changeId"indicates the server uses the field for optimistic locking. The server automatically sets the field's value to the internal transaction number used during the last update of the record. This value changes each time the server updates the record. A table may only have one change tracking field. The field type must be"bigint".The JSON DB API automatically creates a
"changeid"field with change-tracking functionality.Change tracking is optional in the CTDB and ISAM APIs. The application must create a 64-bit integer field and assign change-tracking functionality to it.
The value of this property is the name of the field used for the change-tracking functionality.
If the table already has a change-tracking field, this new field is now used for change-tracking.
The "createRecByteIndex" property is an optional Boolean that creates a special index for quickly walking variable-length records backward when set to true. It defaults to false.
Note
It is not needed for fixed-length records.
The "databaseName" property is an optional string that specifies the database that contains the tables. It defaults to the database name supplied at login.
Note
In the API Explorer, "defaultDatabaseName" is set to "ctreeSQL" in the "createSession" action that happens at login.
A zero-length
"databaseName"is invalid.Its limits are from 0 to 64 bytes.
If the
"databaseName"property is omitted or set tonull, the server will use the default database name specified at login.If no default database is specified during
"createSession","defaultDatabaseName"will be set to the"defaultDatabaseName"value that is specified in theservices.jsonfile.
The "deleteFields" property is an optional array of strings. Each string is the name of a field to remove from a table.
Each string is 1 to 64 bytes.
Removing a field destroys the data in that field.
A zero-length
"fieldName"is invalid.
The "fieldDelimiterValue" property is a decimal number from 0 to 255. It is optional. If omitted, it defaults to 0. The only reason to change it is for backward compatibility with legacy c-tree files.
Set the optional
"fixedLengthRecords"property totrueto optimize the file structure to support only fixed-length fields and records.Each record in the table has a fixed length. This can increase the speed of data processing, but it wastes disk space when strings are highly variable.
Fixed-length records can never contain variable-length fields, such as VARCHAR and VARBINARY.
Fixed-length records do not support Hot Alter Table, which allows a table’s definition to change by rewriting a record’s structure only when it is read or updated.
This command returns an error if any field is not fixed length.
The optional
"growthExtent"property is the number of bytes a file is extended when adding a record exceeds the current size of the file. The default is0bytes, which means a server grows the file using its default algorithm.The optional
"folder"property is the file system path of a folder that will contain the table’s data file. The default is the database folder.The optional
"tableFileExtension"property defines the file extension to add to the table’s name to create the name of the table’s data file. The default is".dat". Meaning a table named"table1"with an extension of".tmp"and a folder of"/temp"stores its data in a data file named"/temp/table1.tmp".The optional
"indexFileExtension"property defines the file extension to add to all index files created on this table. default is".idx". Meaning that an index named"index1"with an extension of".idx"and a folder of"/data"stores the index content in an index file named"/data/index1.idx".Set the optional
"smallFile"property totruewhen you want to optimize for data files smaller than 4 GB. The default isfalse.Small files cannot grow larger than 4 GB and larger data files are fairly common.
To change from a small file to a large file requires a complete file rebuild.
A huge file can grow to over 16 million terabytes. This ensures the file can handle any size of data.
A small file saves index space and increases performance.
A small file requires four-bytes to reference the position of each record in a file.
A huge file requires eight bytes.
A small file saves space on disk and in RAM because each index entry for a small file is four bytes smaller than the same entry for a huge file. This space savings allows for more index entries to be cached and retrieved in a single IO. This increases the speed of inserts, updates, deletes, and index traversals.
The optional
"compression"property defines the type of compression to apply to the table:none (0 in NAV ENUM) - No compression (default)
rle (100 in NAV ENUM) - Runtime Length Encoding reduces size when the data contains the following repeated characters:
space
0
binary 0x00 (NULL)
zlib (200 in NAV ENUM) - This algorithm is slow but becomes efficient when it compresses large amounts of data. For small records (< 200 bytes), the size of the compressed data can be larger than the original.
The optional
"createRecByteIndex"property creates the special purpose RECBYT index when it istrue. The default isfalse.When
false, add the NORECBYT table create option.The RECBYT index enables backward physical traversal of variable-length records. Because it is an extra index, it slows inserts, updates, and deletes. Unless you need to walk variable-length records backward, disable the creation of this index.
The required
"transactionModel"property assigns one transaction model to the table.The property must contain one of the following symbols or be omitted:
"logTransactions"This is the default. The table supports multi-statement ACID transactions and transaction logs. This is the most capable and durable table type. There is very little risk of data loss because committed data is first written to the transaction logs. The table provides atomicity, isolation, consistency, durability, and point-in-time recoverability. Data can be backed up while the database is running with complete data consistency and point-in-time recoverability. Data can be replicated to any other FairCom database.
Use this for excellent durability, full transactional features, data replication, and good performance.
"ctTRNLOG"0in a NAV ENUM(Default)
"ramTransactions"The table supports transactions in RAM without transaction logs. Transactions are processed in memory instead of using transaction logs. Making
"ramTransactions"about 10x faster than"logTransactions". There is a risk of data loss between the time data is committed in memory and when the OS flushes the changes to disk. The table provides atomicity, isolation, and consistency. Data can be backed up while the database is running with complete data consistency but without point-in-time recoverability. Data cannot be replicatedUse this when you need faster performance with transaction processing, but do not need data replication and are willing to potentially lose a few records.
ctPREIMG100in a NAV ENUM
"noTransactions"The table does not support transactions and transaction logs. Data is processed at the fastest speeds. There is a risk of data loss between the time data is written and when the OS flushes it to disk. Data can be backed up while the database is running, but without index consistency and point-in-time recoverability. If data is written to the table during a backup, restoring the backup requires rebuilding the table’s indexes. There is no atomicity. There is some isolation using locks. Data cannot be replicated.
Use this when you want the fastest possible performance, and do not need the benefits of transaction processing and data replication, and are also willing to potentially lose a few records.
CTCREATE_NORMAL200in a NAV ENUM
In
"responseOptions", specifying"dataFormat":"default"or omitting it, is the same as specifying"dataFormat": "objects".
The "growthExtent" property is an optional integer from 0 to 2,147,483,647. It is the number of bytes that a server uses to extend a file. The default value is 0.
A file is extended when adding or updating a record requires a file to grow larger.
Use a larger number to minimize the number of times a file needs to be extended.
Use a smaller number to minimize the amount of unused space in a file.
The "indexFileExtension" property is an optional string from 0 to 64 bytes. It specifies the file system extension to use for a table's index files. If omitted, it defaults to ".idx".
Note
If set to a zero-length string, then newly created index files will have no extension.
The "ownerName" property is an optional string from 1 to 64 bytes that specifies the account that owns an object.
The "padValue" property is a decimal number from 0 to 255. It is optional. If omitted, it defaults to 0.
Fixed-length fields are an optimization for the specific use case of storing fixed-length data that matches the exact length of the field.
For fixed-length fields, the following use cases work well:
Bit flags
A
"binary"field is useful for efficiently storing a fixed set of bit flags where each bit represents a different on/off setting.Legacy identifiers
A
"char"field is useful for efficiently storing legacy fixed-length identifiers, such as a VIN number where characters in specific positions represent different subsets of data.Very small strings
A
"char"field is useful for efficiently storing strings that are smaller than six characters because they do not have the overhead of requiring two extra bytes to track the length of the field.
A fixed-length field is more efficient than a variable-length field because it does not require extra bytes to track the length of the field:
The
"varchar"and"varbinary"fields require two extra bytes to track the length of the field, which can be up to 64K.The
"lvarchar","lvarchar", and"lvarbinary"fields require four extra bytes to track the length of the field, which can be up to 2GB.
Padding is required for fixed-length fields because it is possible to assign data to a field that has a smaller length than the length of the field.
Padding is useful in the following use cases:
The default padding value of
0in a"char"field makes a fixed-length string behave like a variable-length string. It works because the database can treat a fixed-length string as a null-terminated string that can be smaller than the fixed width.A padding value of
32in a"char"field is the ASCII space character, which automatically left-aligns fixed-length strings.The default padding value of
0in a"binary"field works for bit flags when zero is the desired default state of a bit. Otherwise, padding in a"binary"field is rarely a good thing because it alters the binary value.
When the server assigns a value to a
"char"or"binary"field (which are fixed-length field types), it puts the value in the field starting on the left and uses the pad value to fill in any remaining bytes on the right.In other words, when the number of bytes in a value being assigned to a
"char"or"binary"field is less than the number of bytes in the field, the server fills in the remaining bytes with the pad value.
The default pad value of
0causes a special padding behavior for"char"fields.It causes the JSON DB API to treat fixed-length string fields as if they were variable-length strings with a maximum length.
In other words, the same string value going into a
"char"field comes out the same, no padding is added — for example, when a table's"padValue"is set to0and a JSON string of"12"is inserted into a"char"field, the JSON string of"12"is returned from that field.
When you want the server to add padding to strings that are stored in a
"char"field, set the"padValue"property to a non-zero number that is the ASCII character you want to pad the string.For example, set
"padValue"to32to pad strings with the space character. When a table's"padValue"is set to32and a JSON string of"12"is inserted into a"char"field with a"length"of4bytes, the JSON string of"12 "is returned from that field.
The server always applies padding when the number of bytes in a binary value is less than the number of bytes in the fixed length,
"binary"field. When the server adds padding to a binary value, it permanently modifies the binary value. If this is not desirable, ensure the binary value exactly matches the size of the"binary"field.The JSON DB API always returns the entire stored value of a
"binary"field. This binary value is encoded as a JSON string containing a base64 or hexadecimal representation of the binary value. The length of the JSON string encoded in base64 or hexadecimal is always longer than the length of the binary field.If a table's
"padValue"is set to0, and a binary value of0x3132is stored in a"binary"field with a"length"of4bytes, the server pads the value and stores the value of0x31320000into the field. When the value is returned by the JSON DB API, it is returned as0x31320000. Thus, padding alters a binary value when the value is smaller than the field. The default padding behavior of a"binary"field is different from the default padding behavior of a"char"field because the server can assume that anASCII NULLpadding value is a string terminator, but it cannot assume the same for a binary value.
If a table's "padValue" is set to 0, the ASCII NULL character with the hexadecimal value of 0x00 is used to pad unfilled byte positions. So when the JSON string "12" is inserted into a "char" field that has a "length" of 4 bytes, the binary value of 0x31320000 is stored in the field. When the JSON DB API retrieves the value, it returns it as JSON string of "12" because it recognizes the ASCII NULL character as a string terminator.
In other words, the ASCII NULL character allows the server to automatically trim the length of a string that is stored in a fixed-length field before it returns the string in JSON. So, by default, the same JSON string inserted into a "char" field is always returned by the JSON DB API. This behavior is safe for UTF-8 strings, which is the string encoding used by JSON.
When a table's "padValue" is set to 32, which is hexadecimal 0x20, and a JSON string of "12" is assigned to a "char" field that has a "length" of 4 bytes, the binary value of 0x31322020 is stored in the field. When the JSON DB API retrieves the value, it returns it as a JSON string of "12 ". This is because the value 32 is the ASCII space character " ".
If a table's "padValue" is set to 54, which is hexadecimal 0x36, and a JSON string of "12" is assigned to a "char" field that has a "length" of 4 bytes, the binary value of 0x31323636 is stored in the field. When the JSON DB API retrieves the value, it returns it as a JSON string of "12--". This is because the value 54 is the ASCII character "-".
Assigning "12**" to a "char" field that has a "length" of 4 bytes, stores "12**" into the field regardless of the table's "padValue".
Assigning " $12.34" to a "char" field that has a "length" of 8 bytes, stores " $12.34" into the field regardless of the table's "padValue".
Use the variable-length char and binary field types ("varchar", "lvarchar", "lvarchar", "varbinary", and "lvarbinary").
Each of these field types are stored in the table with length information, so the data returned matches the data stored.
This property specifies the fields to use for the table’s primary key.
The "primaryKeyFields" property creates a unique "primary key" index on these fields. |
The index is named "field1_fieldN_pk" where field1 through fieldN are the names of the specified fields. |
When the table already has a primary key index, altering a table with this property may create an additional "primary key index". |
The user can use "deleteIndexes" to remove extra indexes. |
The "tableName" property is a string containing the name of a table.
A table name may contain up to 64 ASCII characters and must not start with a number.
The "transactionModel" property is an optional, case-insensitive, string enum. It defines how the server processes transactions for a table. The default is "logTransactions".
"logTransactions"This persists data to data files and writes transaction changes to transaction logs. It supports commit and rollback transactions and data replication. It will not lose data during an unplanned outage. It provides the most durability and the most capabilities but is slower than the other settings.
"ramTransactions"This supports commit and rollback transactions in RAM while persisting data to data files. It does not use a transaction log, which makes it even faster, but an unplanned outage may lose or corrupt unwritten data.
"noTransactions"This does not support transactions but still persists data to disk. This makes it even faster, but an unplanned outage may lose or corrupt unwritten data.
Properties summary
"result" property summariesProperty | Description | Type | Limits (inclusive) | |||
|---|---|---|---|---|---|---|
data | contains an array or object that the server returns, such as records returned by a query. It is an empty array when there are no results available | array | Its contents are determined by the action | |||
defines the format of the data in the | string |
|
The "dataFormat" property is an optional, case-insensitive string enum that defines the format of the response in the "data" property. The default format is an array of arrays. The alternative is an array of objects. The default for "dataFormat" can be changed during a "createSession" action by assigning a different value to the "dataFormat" property in "defaultResponseOptions".
"dataFormat" property:Two of those versions occur in a request and another occurs in a response. They all indicate how data is formatted.
"dataFormat"in the request inside"responseOptions"determines how the"data"property in the response is formatted.Possible values include:
"arrays"This is the default and causes the server to return results as an array of arrays, which is the most efficient.
"objects"This returns results as an array of objects. This is less efficient but is simpler to generate, read, and troubleshoot.
"dataFormat"in the request in the"params"object notifies the server how the"sourceData"property is formatted in the request. This version is rarely used because of the default"autoDetect"behavior.Possible values include:
"arrays"This causes the server to return results as an array of arrays, which is the most efficient.
"objects"This returns results as an array of objects. This is less efficient but is simpler to generate, read, and troubleshoot.
"autoDetect"This is the default and causes the server to automatically detect the format of the data in the
"sourceData"property.
"dataFormat"in the response shows the client how the server formatted the"data"property.Possible values include:
"arrays"This is the default and causes the server to return results as an array of arrays, which is the most efficient.
"objects"This returns results as an array of objects. This is less efficient but is simpler to generate, read, and troubleshoot.
You cannot modify a table while it is in use. When a table has no activity for a default of 2 seconds, it will be closed so you can modify it.
When a table is in use, the following actions return an error, such as -8 or 4012:
"alterTable"
"rebuildTables"
"deleteTables"
"createIndex"
"deleteIndexes"
"rebuildIndexes"
"runSqlStatements"
A table is in use when any account is performing one or more of the following actions with the table:
"insertRecords"
"updateRecords"
"deleteRecords"
"truncateRecords"
"getRecords..."
Has open cursors on the table.
Has open transactions on the table (such "createTransaction").
Modify the
SQL_IDLE_WAKEstartup configuration setting to change the number of seconds the server waits before closing a table. A larger number keeps the table open longer for better performance. A smaller number allows you to modify the table sooner.Modify the
SQL_IDLE_WAKEstartup configuration setting to change the number of tables the server keeps open after they are no longer being actively used. A larger number caches more tables and improves performance. A smaller number allows you to modify tables sooner.