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src/providers/mssql/purgeSql.js

@@ -1,6 +1,6 @@
 /** Drop order = reverse of schema create dependency order. */
 export const TABLES = [
-  
+  'healthcheck',
   'articlewarehousesummary',
   'deliverysummary',
   'shipmentsummary',

src/providers/mssql/queries/healthcheck.js

@@ -0,0 +1,19 @@
+export const ENSURE_ROW = `
+IF NOT EXISTS (SELECT 1 FROM healthcheck)
+BEGIN
+    INSERT INTO healthcheck ([sequence]) VALUES (0);
+END
+`;
+
+export const SELECT_FOR_UPDATE = `
+SELECT TOP 1 id, [sequence]
+FROM healthcheck WITH (UPDLOCK, ROWLOCK)
+ORDER BY id ASC;
+`;
+
+export const UPDATE_SEQUENCE = `
+UPDATE healthcheck
+SET [sequence] = @sequence,
+    updated_at = SYSUTCDATETIME()
+WHERE id = @id;
+`;

src/providers/mssql/schema.js

@@ -1437,8 +1437,20 @@ BEGIN
 END
 `;
 
+export const INIT_HEALTHCHECK = `
+IF NOT EXISTS (SELECT * FROM sys.tables WHERE name = 'healthcheck')
+BEGIN
+    CREATE TABLE healthcheck (
+        id INT IDENTITY(1,1) PRIMARY KEY,
+        [sequence] BIGINT NOT NULL CONSTRAINT DF_healthcheck_sequence DEFAULT 0,
+        updated_at DATETIME2 NOT NULL CONSTRAINT DF_healthcheck_updated_at DEFAULT SYSUTCDATETIME()
+    );
+END
+`;
+
 /** DDL scripts in dependency order for schema init. */
 export const SCHEMA_SCRIPTS = [
+    INIT_HEALTHCHECK,
     INIT_META,
     INIT_LANGUAGE,
     INIT_TAX,